Devender

The Fields Around Us: How Fundamental Forces Shape Our Lives

2024-08-11T15:36:00.006-04:00

In the grand tapestry of the universe, everything we see, touch, and experience is governed by a delicate interplay of fundamental forces. From the vast expanses of space to the intricate workings within our own bodies, these forces shape our reality in profound ways.

Each of these forces – electromagnetism, gravity, the weak nuclear force, and the strong nuclear force – has a field associated with it. Just as a magnet creates a magnetic field around it, all objects with mass create a gravitational field. These fields, invisible to the naked eye, exert forces on other objects within their reach.

Einstein's groundbreaking theory of general relativity describes gravity not as a force pulling objects together, but as the curvature of spacetime caused by the presence of mass. Imagine a bowling ball on a trampoline; it creates a depression, causing other objects to roll towards it. Similarly, massive objects distort the fabric of space itself, creating what we perceive as gravity.

Electromagnetism, on the other hand, can be both attractive and repulsive. Positive and negative charges attract, while like charges repel. This duality gives rise to the rich complexity of chemical bonds and the flow of electricity. Gravity, however, is solely attractive.

As humans, we are made of the same fundamental particles that experience these forces. We are constantly interacting with fields, both within our own bodies and from the world around us.

Just as atoms and molecules are attracted or repelled by electromagnetic forces, we too experience forces of attraction and repulsion in our relationships with others. The company we keep, the people we surround ourselves with, can have a profound impact on our mindset and well-being.

Positive relationships, like supportive friendships and loving families, can uplift us and help us thrive. They provide a sense of belonging and security, fostering growth and happiness. Negative relationships, however, can drain our energy and create stress. Toxic people or unsupportive environments can hinder our progress and leave us feeling depleted.

It is essential to recognize the power of these forces in our lives. Just as we are drawn to positive influences, we are also susceptible to negative ones. We have the power to shape our reality by choosing the company we keep.

My advice is simple: remove people or influences that negatively impact you. Surround yourself with individuals who support and uplift you. Cultivate relationships that foster growth and happiness. Remember, the fields around us are constantly interacting, shaping our experiences. By choosing positive influences, we can create a life filled with joy and fulfillment.

The Energy of Existence: Einstein, Thermodynamics, and the Hindu Perspective

2024-07-14T15:07:00.003-04:00

Have we not all considered that we might be more than just flesh and bone? That the essence of who you are is pure energy? It's not just a philosophical concept; it's backed by science and ancient wisdom.

Einstein's Equation: More Than Just Physics

Most of us have seen Einstein's famous equation, E=mc². It's more than a mathematical formula; it's a profound statement about the nature of reality. It tells us that energy (E) and mass (m) are interchangeable, connected by the speed of light squared (c²). We are made of matter, and matter is energy.

Thermodynamics and the Cycle of Energy

The laws of thermodynamics reinforce this idea. They state that energy cannot be created or destroyed, only transformed. Think of it like this: the chemical energy stored in your food becomes the energy you use to walk, talk, and think. It might even power the light bulb illuminating this blog post. Your energy is constantly in flux, changing forms.

The Hindu View: Rebirth and Energy Transfer

Hinduism, one of the world's oldest religions, has long held a similar view. The concept of reincarnation suggests that our soul (or Atman) is a form of energy that transmigrates from one body to another after death. This isn't so different from the scientific view of energy transformation, is it?

Where Will You Put Your Energy?

If we accept the idea that we are energy, and that energy is constantly changing and moving, then it raises an important question: Where are you putting your energy?

We have a finite amount of time in our human form. Our energy, in this particular incarnation, is limited. The work we do, the relationships we nurture, the hobbies we pursue – these are all ways we channel our energy. Are you resonating with where your energy is flowing?

Finding Your Energy Alignment

Self-Reflection: Take time to examine where your energy is currently focused. Are you happy with how it's being used?
Set Intentions: Decide how you want to direct your energy. What brings you joy and fulfillment?
Make Conscious Choices: Align your actions with your intentions. This might mean changing jobs, pursuing a new passion, or simply spending more time with loved ones.

Embrace Your Energetic Nature

By recognizing ourselves as energy, we open the door to a deeper understanding of our existence and our purpose. We realize that we are not just individuals, but part of a larger energetic dance. This knowledge empowers us to make conscious choices about how we use our precious energy, ensuring that it resonates with who we truly are.

Let's make the most of our time in this human form. Let's choose to vibrate at a frequency that brings us joy, fulfillment, and a sense of interconnectedness with the world around us. After all, we are all energy.

Is Time the Entropy of Quantum Mechanics?

2024-05-19T18:34:00.002-04:00

Is Time the Entropy of Quantum Mechanics?

Time is a fundamental concept in our everyday lives, yet its true nature remains elusive. In thermodynamics, entropy measures disorder or randomness in a system. Could there be a deeper connection between time and entropy, especially in the realm of quantum mechanics?

Thermodynamics & Entropy: Entropy always increases in a closed system, giving us the "arrow of time."
Quantum Mechanics & Uncertainty: Quantum systems are probabilistic, their future states uncertain.
A Daring Hypothesis: Could this quantum uncertainty be the source of entropy, and therefore the driving force behind time?

If time is simply the manifestation of increasing quantum entropy, it could revolutionize our understanding of the universe.

Disclaimer: This is a theoretical exploration and not a proven scientific theory.

#quantumphysics #time #entropy #science

Exploring the Harmony of Opposites: The Influence of Chinese Thought, Taoism, and Zen on Modern Perspectives

2024-03-01T23:15:00.002-05:00

In the realm of philosophy, the rich tapestry of Chinese thought has woven itself into the very fabric of how we perceive and interact with the world around us. From the dynamic interplay of yin and yang to the mystical currents of the Tao, these ancient philosophies offer insights that resonate with startling relevance in our contemporary lives. Among these, Zen Buddhism stands out as a fascinating synthesis, primarily Japanese in its practice, yet deeply rooted in Chinese philosophical traditions, especially Taoism.

Yin and Yang: Confucius vs. Taoism: The concept of yin and yang captures the essence of duality and balance within the universe, illustrating the profound interdependence of opposite forces. In an intriguing observation, it's noted that Taoism, with its emphasis on fluidity, spontaneity, and the feminine aspect, serves as a counterbalance to the more structured, masculine, and dominating principles of Confucianism. This dichotomy is not static but dynamic, reflecting a journey of personal growth and transformation. As individuals age, there is a noticeable shift from the youthful embrace of Confucian order towards the liberating Taoist flow, suggesting a natural progression towards seeking harmony and balance in one's life.

Chi, Acupuncture, and Change: Central to Chinese philosophy is the concept of chi (qi), the vital life force that flows through all things. Acupuncture, a practice rooted in the manipulation of this energy, embodies the principle of maintaining balance within the body. Similarly, the I-Ching, with its hexagrams, represents the ever-present potential for transformation. These traditions underscore a core Taoist belief in the importance of harmony, transformation, and wu-wei (non-action or effortless action), reminding us of the constant flux and the possibility of aligning with the natural order to achieve well-being.

Zen: A Unique Blend: Zen Buddhism represents a unique convergence of Buddhist, Taoist, and Confucian elements, crafting a path to enlightenment that embraces both action and contemplation. The practice of Zen, with its rituals like the tea ceremony and the use of koans (paradoxical anecdotes or riddles), encourages a departure from conventional thought and a deeper engagement with the present moment. This blend of discipline, intuition, and sudden insight reveals the profound influence of Chinese thought on Zen, highlighting a holistic approach to spiritual awakening.

These discussions illuminate a fundamental truth at the heart of Chinese philosophy: the power of embracing opposites to find balance. This principle manifests in various aspects of life, from the societal balance between order and spontaneity to the personal journey towards integrating rational thought with intuitive understanding. Zen Buddhism, with its roots in Taoism and its branches reaching into the essence of mindfulness and enlightenment, offers a compelling example of how these ancient philosophies continue to shape our quest for harmony and understanding.

RISC: Simplifying Complexity in the World of Computer Architecture

2024-02-25T11:41:00.006-05:00

The landscape of computer architecture has undergone significant transformations over the decades, evolving from the intricacies of assembly language to the sophisticated high-level programming languages of today. Central to this evolution has been the development and refinement of the Instruction Set Architecture (ISA), a vital link between software and hardware that defines the machine operations, data types, registers, and the memory model of a computer. The beauty of ISA lies in its ability to abstract the complexities of hardware into a manageable set of instructions for compilers to convert code efficiently.

In the 1980s, a revolutionary concept emerged that would redefine the efficiency and performance of computer systems: Reduced Instruction Set Computing, or RISC. RISC architecture advocates for a simplified, more streamlined set of instructions, in stark contrast to the Complex Instruction Set Computing (CISC) that dominated the era with its extensive and intricate instruction sets. The philosophy behind RISC centers on the realization that a reduced ISA, typically around 50% smaller than its CISC counterparts, can lead to substantial improvements in performance and power efficiency.

One of the standout features of RISC architecture is its ability to significantly reduce the number of clock cycles per instruction—from, say, 10 cycles in traditional systems down to just 2 cycles. While this might necessitate doubling the number of instructions for certain operations, the overall gain in speed and reduction in power consumption are undeniable advantages. This efficiency leap is particularly beneficial in the realm of embedded devices and emerging technologies, where power efficiency and performance are paramount.

The advent of RISC-V (5th version), an open-standard ISA based on RISC principles, marks a significant milestone in the journey of RISC architecture. With around 40 key instructions, RISC-V offers a universal platform on which all software can theoretically run. This universality makes it especially optimal for machine learning accelerators, which primarily rely on matrix multiplication. The open nature of RISC-V encourages innovation and development, allowing for tailored software solutions that can leverage the architecture's inherent efficiencies.

Embedded devices, from IoT gadgets to sophisticated cloud infrastructure, stand to benefit immensely from the adoption of RISC architecture. The reduced instruction set not only simplifies the hardware design but also lowers power consumption—a critical factor for devices that require long battery life or operate in power-sensitive environments. Moreover, the scalability of RISC architecture means it can easily adapt to the burgeoning demands of cloud computing, albeit with the caveat that transitioning to new software frameworks may necessitate a period of adjustment and code rewriting.

Looking ahead, the trajectory of RISC and its impact on the future of computing appears promising. As more industries and technologies pivot towards embedded systems and machine learning, the principles of RISC—efficiency, simplicity, and power conservation—will likely become ever more relevant. The challenge, however, lies in balancing the need for backward compatibility with the relentless push for innovation. As we navigate this delicate balance, the beauty of ISA and the elegance of RISC architecture will undoubtedly continue to play a pivotal role in shaping the next generation of computing technologies.

Multivariate Modeling and Probabilistic Output: Transforming the Semiconductor Industry

2024-02-24T14:08:00.002-05:00

In the rapidly advancing world of technology, the semiconductor industry stands at the forefront, driving innovations that power everything from consumer electronics to critical infrastructure. The ability to accurately model and predict outcomes is crucial for maintaining efficiency, optimizing processes, and innovating at pace. This is where multivariate modeling and probabilistic output come into play, offering powerful tools that are transforming the semiconductor industry.

Understanding Multivariate Modeling

Multivariate modeling involves analyzing multiple variables simultaneously to understand their relationships and impact on a particular outcome. Unlike univariate models that consider only one predictor variable at a time, multivariate models can handle the complexity and interconnectedness of real-world data, making them especially suited to the semiconductor manufacturing process.

In semiconductor fabrication, for example, variables such as temperature, pressure, chemical concentrations, and timing must be precisely controlled and coordinated. Multivariate analysis allows engineers and scientists to understand how these variables interact with each other, providing insights into how changes in one area can affect the entire process.

The Role of Probabilistic Output

Probabilistic output, a key feature of advanced statistical methods like Bayesian statistics, bootstrapping, and Monte Carlo simulation, offers a way to quantify uncertainty in predictions and model estimates. Rather than providing a single point estimate, probabilistic outputs give a range of possible outcomes along with their probabilities. This is invaluable in decision-making processes where risk and uncertainty are inherent, as is often the case in semiconductor manufacturing.

Why It's Needed in the Semiconductor Industry

The semiconductor industry is characterized by its high complexity, tight performance tolerances, and rapid pace of innovation. Here's why multivariate modeling and probabilistic output are particularly necessary:

Complex Process Optimization: The manufacturing process for semiconductors involves hundreds of steps, each with multiple variables affecting the outcome. Multivariate modeling enables the optimization of these processes by identifying the most significant variables and their interactions.

Quality Control and Yield Prediction: By applying probabilistic output, manufacturers can predict the likelihood of defects or failures, allowing for more effective quality control and yield management. This approach helps in identifying potential issues before they become costly problems.

Risk Management: In an industry where the financial stakes are high, being able to quantify risk and uncertainty helps companies make better-informed decisions. Probabilistic outputs provide a framework for assessing the likelihood of various outcomes, enabling more robust risk management strategies.

Innovation and Development: Developing new semiconductor technologies requires navigating uncharted territories. Multivariate modeling facilitates the exploration of new material properties, device architectures, and manufacturing techniques by allowing researchers to simulate and predict the effects of multiple variables.

Supply Chain and Logistics Optimization: The global nature of the semiconductor supply chain introduces additional complexity and uncertainty. Multivariate models can help optimize logistics and supply chain management by considering multiple factors such as demand forecasts, production capacity, and transportation logistics.

Conclusion

As the semiconductor industry continues to evolve, the adoption of multivariate modeling and probabilistic output is becoming increasingly critical. These methodologies offer the ability to navigate the complexities of semiconductor manufacturing, manage risks more effectively, and accelerate innovation. By leveraging the insights provided by multivariate analysis and embracing the quantification of uncertainty, the semiconductor industry can continue to thrive in an era of unprecedented challenges and opportunities.

[Part 2] Unveiling the Secrets of Subatomic Reality

2024-02-23T17:06:00.006-05:00

Introduction

The world we perceive is built from atoms – those seemingly simple building blocks taught in school. But zoom in further, and the picture gets much more complex. Electrons whirl around a dense nucleus made of protons and neutrons, and within that nucleus, even more mysteries unfold.

Let's dive into the strange and fascinating realm of subatomic particles.

Quantum Weirdness and the Heart of the Atom

- Electrons don't orbit like planets. They exist as probability waves described by quantum numbers, buzzing around the nucleus in specific energy states.

- The nucleus itself is ruled by the powerful strong nuclear force, keeping protons and neutrons incredibly tightly packed despite the repulsive electric force between protons. This force decays rapidly with distance, explaining why it's undetectable outside the nucleus.

A Zoo of Particles and the Limits of Theory

- High-energy experiments revealed a whole menagerie of subatomic particles beyond the familiar few. Most of these are short-lived, suggesting that what we think of as fundamental particles might actually be different states of energy. Think of antimatter (like positrons), which can be created when energy is concentrated.

- Shockingly, we still lack a theory that unites the quantum world (which governs the very small) and relativity (which governs the very large and fast). This means the inner workings of the nucleus remain somewhat of a puzzle.

Forces as Exchange Particles

- The most mind-bending concept is that forces themselves aren't invisible tugs, but rather result from the exchange of other particles. Electromagnetic force? That's photons being tossed around. The strong nuclear force? That's gluons acting as the glue between particles within the nucleus. This paints a picture of a universe not made of separate 'things' but of interconnectedness and exchange.

Conclusion

Subatomic physics challenges our intuition. The deeper we look, the less tangible matter becomes. Our search for fundamental building blocks may reveal that reality is ultimately about relationships and transformations, not about isolated, unchanging objects. Where this journey will lead is anyone's guess, but it forces us to rethink what we mean by the very word "existence."

[ Part 1] Unraveling the Fabric of Reality: From Newton to Quantum Mechanics

2024-02-22T12:25:00.006-05:00

In the grand tapestry of scientific discovery, the evolution from classical physics to quantum mechanics and relativity theory represents a profound shift in our understanding of the universe. This journey, marked by groundbreaking insights and paradigm-shifting concepts, reveals the complex and often counterintuitive nature of reality.

At the heart of this scientific revolution was Isaac Newton, whose conception of fixed space and time laid the foundation for classical mechanics. Newton's development of differential calculus and the laws of motion ushered in an era of rigorous determinism, where the cosmos was seen as causal and determinate. Early gaps in these calculations were attributed to divine intervention, a notion later dispensed with by Laplace, who resolved these mathematical inconsistencies.

While Newtonian mechanics excelled in explaining fluid dynamics and the theory of heat, it stumbled when confronted with the electromagnetic experiments of Faraday and Maxwell. It was Maxwell's introduction of the concept of the electromagnetic field, or electrodynamics, that challenged the Newtonian paradigm. This notion of a force field existing independently of object interaction was revolutionary, differing fundamentally from the direct, interaction-based forces of Newtonian mechanics.

Maxwell himself grappled with these ideas, initially attempting to reconcile them with the concept of ether. However, it was Einstein who recognized electromagnetic fields as physical entities in their own right, capable of propagating through empty space. This recognition was a crucial step away from the ether theory and towards a new understanding of the universe.

The introduction of relativity theory and atomic physics further dismantled the classical concepts of absolute space and time. Solutions to the Schrödinger equation, for instance, showed that electrons could only occupy certain energy levels, introducing the concept of band gaps in solid-state physics. Einstein's general theory of relativity, positing that gravity can bend space-time, challenged Euclidean geometry and the very fabric of our understanding of the universe.

Rutherford's experiments, revealing that atoms are mostly empty space, along with the dual nature of subatomic particles, underscored the quantum leap in our comprehension of matter. The discovery of quanta of energy by Max Planck, and the realization that photons are massless particles traveling at the speed of light, further highlighted the departure from deterministic laws.

Perhaps most disruptively, the uncertainty principle demolished the classical laws of determinism, introducing a probabilistic framework to the behavior of particles at the quantum level. This principle, emphasizing the inherent limitations in measuring both the position and momentum of particles, underscores the fundamental unpredictability at the heart of quantum mechanics.

The transition from Newton's deterministic universe to the probabilistic realms of quantum mechanics and the curved space-time of relativity reflects a monumental shift in scientific thought. It challenges us to rethink our place in the universe, the nature of reality, and the laws that govern it. In this journey, we find not just the intricacies of the physical world, but a deeper harmony in nature's laws, as envisioned by Einstein. This evolution of thought, from the mechanics of the macroscopic world to the quantum and relativistic realms, continues to inspire and challenge our understanding of the cosmos.

Exploring the Paradoxes: Beyond Language with Buddhism, Quantum Mechanics, and Linguistics

2024-02-20T20:25:00.004-05:00

In the intriguing intersection of spirituality, science, and linguistics, the works of TJ Suzuki and Heisenberg present a compelling narrative that transcends conventional understanding. They delve into the realms of Buddhism and atomic structure, suggesting that these ancient wisdoms and modern scientific discoveries share a common ground beyond the realm of language.

Buddhism, with its profound teachings on the nature of reality and existence, parallels the complex and often counterintuitive world of quantum mechanics, as observed in the behavior of atoms and subatomic particles. This intersection is not merely a coincidence but a reflection of the universal truths that govern our existence, transcending the boundaries of language and conventional logic.

The dual nature of electromagnetic radiation serves as a perfect metaphor for this convergence. Light exhibits wave-like characteristics when it emanates from two sources, creating an interference pattern that speaks to the interconnectedness of all things, a principle deeply embedded in Buddhist philosophy. Conversely, its particle-like properties, as observed in the photoelectric effect where photons kick out electrons from a metal surface, echo the Buddhist notion of the momentary and discrete nature of reality.

Koans, the enigmatic and paradoxical questions used in Zen Buddhism to transcend rational thought and provoke enlightenment, offer a method to engage with these scientific phenomena on a deeper level. Just as koans challenge the mind to abandon linear thinking and embrace the paradox, the dual nature of light invites us to reconsider our understanding of the physical world. It suggests that reality, at its core, is not bound by the binary constraints of language or the human intellect.

TJ Suzuki and Heisenberg illuminate the idea that both science and spirituality seek to answer the same fundamental questions about the universe and our place within it. Their work draw a parallel between the structure of the atom and the teachings of Buddhism, though seemingly disparate, are interconnected strands of the same fabric of existence. By transcending the limits of language, they offer us a glimpse into the profound unity of all things.

This exploration invites us to consider the ways in which language shapes our understanding of the world and the limits it imposes on our comprehension of the vast, interconnected web of existence. It challenges us to look beyond words and concepts, to embrace the paradoxical nature of reality, and to find harmony in the seeming contradictions of the universe.

As we delve deeper into the mysteries of the universe, both through the lens of science and the wisdom of ancient philosophies, we are reminded of the importance of remaining open to the unknown. The journey beyond language, into the heart of paradox, is not merely an intellectual exercise but a spiritual quest that has the power to transform our perception of the world and our place within it.

Knowing and Seeing: Unveiling the Dance Between Language and Consciousness

2024-02-19T12:21:00.002-05:00

Our understanding of the world is shaped by an intricate interplay between knowing and seeing. But what is the nature of this knowledge, and how does the language we use to express it influence our perception?

At its core, knowledge exists in two distinct realms: rational and intuitive. The rational mind, often associated with science, thrives on logic, analysis, and abstraction. It dissects the world into symbols and equations, seeking quantifiable truths. Think of a map: it represents the territory, but it is not the territory itself. It allows us to navigate, but it cannot capture every nuance and detail.

On the other hand, the intuitive mind, often linked to religion and spirituality, embraces holistic understanding and interconnectedness. It seeks absolute truths that transcend the limitations of reason. It's the feeling of awe gazing at a starry night, a knowing that goes beyond words.

Language plays a crucial role in mediating these two forms of consciousness. Rational language excels at precision and clarity, using abstraction to categorize and analyze the world. Yet, it can also be limiting, as it cannot encompass the full richness and complexity of our experience. The map, once again, becomes a metaphor: we can describe the features of the territory using language, but the true essence of the journey remains ineffable.

The scientific method, with its emphasis on experimentation, theory, and prediction, exemplifies the strengths of rational language. However, even here, intuition plays a crucial role. The spark of an idea, the hunch that guides experimentation, often arises from the realm beyond logic.

Language, in its beautiful ambiguity, becomes a paradox. For the poet, the scientist, and everyone in between, it is both a tool and a limitation. In science, particularly in mathematics, language strives for precision and rigor, using rules and logic to constrain meaning. Yet, for the poet, it is a playground of possibility, where ambiguity and nuance paint tapestries of emotion and imagination.

Ultimately, the dance between knowing and seeing is a lifelong exploration. It is in the interplay between rational and intuitive modes of understanding, and the nuanced language we use to express them, that we begin to unveil the mysteries of the world and ourselves.

How LEDs work and a short guide on Semiconductors

2015-03-31T15:08:00.002-04:00

Before explaining how Light Emitting Diodes (LEDs) work, let me give a quick introduction on semiconductor. Semiconductors are not good conductors of electricity due to very few free electrons (about 4-6 orders less free electrons than metals). This has to do with chemical bonding in the semiconductors, check this post. But, semiconductors can be manipulated by doping them with foreign elements to increase the number of free electrons. Let us take Silicon (Si) for example, Si has 4 covalent bonds with 4 adjacent Si atoms. If we dope Si with Phosphorous or Arsenic (P and As), we will end up with one extra free electrons as P or As can form 5 bonds. Similarly if we dope Si with either Boron or Alumnium (B and Al), we will end up with a free hole (absence of electrons, these can conduct electricity too) as B and Al can only form 3 bonds.

(Source of the image: LINK)

Doping is know as n-type if it results in an extra electron and p-type if an extra hole is created. An electron can combine with hole to release energy in a form of photon.

Now, let us come back to Light Emitting Diodes (LEDs). LEDs are made from combination of a p-type semiconductor and a n-type semiconductor. This combination is connected to a source of current (batttery or A/C power supply). Now when charge starts to flow in LEDs, one of the electron can combine with one of the hole to produce a photon (basically elementary particle of the light). And that's how LEDs work.

(Source of the image: LINK)

How do solar cells work?

2015-03-30T15:55:00.003-04:00

Introduction
Solar cell convert solar energy directly into electric energy using a phenomenon known as photoelectric effect and that is why there are also known as Photovoltaics. Photoelectric effect in simple terms is release of electron due to absorption of a Photon. As I have already described in one of the podcast here that electrons reside in specifically defined states by rules of quantum mechanics. So, when a photon strikes an atom, one of the electrons can be knocked loose and can be captured into a circuit using electrode thereby converting solar energy into electric energy.

(Source of the gif: http://www.bluffton.edu/courses/TLC/MontelA/Montel/Alternative_Energy_Website/jenaefinal.gif)

Science behind
Typically, number of solar cells are connected to each other and combination is known as Solar panels. Common solar cells are made from a junction which are engineered in a way that photons energy is greater or equal to the band gap. Band gap is an energy range in which no electrons can reside as per rules of quantum mechanics.

(Source of the image: http://en.wikipedia.org/wiki/Band_gap)

Photons with energy lower than the band gap at the junction will not be able to create electrons. Silicon and Gallium Arsenide are the common materials used in solar cells. In the commercial solar cells, multiple junctions are engineered with varying energy gaps to use as much of the sun's spectrum as possible.

Efficiency and future
Efficiency of single junction are limited to 34% but this has been eliminated by using multijunctions and current record is around 44% at the lab scale. For commercial solar panels, efficiency range from 10-17%. Apart from intrinsic characterisitics of the junction, efficiency of solar cells is also dependent on how much sun's spectrum can be used and how much sun light can be concentrated on the solar cells for a given area. So, active area of research in photovolatics is on three area:
- Finding new multijunctions and putting these materials together
- Solar concentrators- to collect more sun light on a given area
- Engineering band gap of material

Why is sky blue and grass green?

2015-03-28T19:09:00.001-04:00

First off, our eyes can only detect a small portion of electromagnetic spectrum known as visible region (400-700 nm in wavelength). Our retina has no sensitivity for radio, x-rays and other radiations outside of visible region.

(Source of image: http://www.sun.org/encyclopedia/electromagnetic-spectrum)

Color by reflection
Color in a substance can be produced from various mechanisms, most common of which is the reflection. An object is red because it absorbs all the color except red which is reflected back and detected by retina in our eyes. Grass is green because it produces a pigment name Chlorophyll (used for photosynthesis). Chlorophyll is a stronger absorbed of red and blue light and reflects green color and hence the color of the grass.

Color by scattering
But reflection is not the only mechanism by which color is produced like color of sky can be explained by a scattering phenomenon knows as "Rayleigh Scattering". Rayleigh found that scattering power of particles in inversely related to wavelength. Now, blue light has the smallest wavelength in visible region and hence strongly scattered by particles in the sky leading to blue color of the sky. But during sunset we see red color? During sunset sky appears yellow, orange or red (depending on atmosphere around you) because most of the blue light is already scattered and long-range wavelength colors are what left for us to see.

(Source of the image: http://math.ucr.edu/home/baez/physics/General/BlueSky/blue_sky.html)

Color by radiation and electronic transition
Color can also be produced by radiation when a body is hot or due to electrons transitions. We already discussed in this post that a hot object can produce electromagnetic radiations via motion of atoms. One more mechanism of color is related to electrons. Electrons in an atom occupy specified states determined by quantum mechanics. By some sort of mechanism (heat etc.), these electrons can be excited to higher states and after sometime electrons would fall back to their original states and in doing so, releases photons of various wavelength. This phenomenon is used in LEDs bulbs. I will write a detailed post on that sometime in future.

How was the universe created? The Big Bang Theory

2015-03-27T16:47:00.001-04:00

Our Milky Way has more than 100 billion stars and there are billions of galaxies in the universe. So an obvious question is how it all started?

Postulation

Humans have been trying to figure this out for centuries and ironically most accepted theory today was first proposed by a theologian named George Lemaitre in early 1927. It did not gain momentum until an astronomer named Edwin Hubble (Hubble telescope named after him) found out that Universe is expanding. This led many to theorize that if universe is expanding so it must have been started as tiny and dense point. Hubble was mocked for years and in fact the name "Big Bang Theory" was coined sarcastically by astronomer Fred Hoyle.

Evidence?

It was an accidental discovery in 1964 by astronomer Wilson and Penzias that led to second experimental evidence (first being expansion of the universe) for Big Bang Theory. They discovered persistent radio signal in their antennas which is attributed to energy photons released just after (10^-32 second) the Big Bang.

(Source of the image: http://map.gsfc.nasa.gov/universe/bb_tests_cmb.html)

Explaining how universe formed?

According to the Big Bang Theory, all the matter was contained inside a single, minute point which bursted about 13 billion years ago. Universe expanded at tremendous rate, doubling every 10^-34 second. Huge amount of energy was created due to the burst. This energy was converted into matter and antimatter which kept on recombining to annihilate but also kept on forming due to very high temperature (billions of degrees of Kelvin). After few seconds, universe started to cool down and at some point of time there was not enough energy for creation of matter and antimatter. And luckily for us, annihilation (combination of matter and antimatter) was probabilistic and not all the matter annihilated. After minutes of the Big Bang, electrons and protons were created from the matter which further led to formation of atoms of basic elements of Hydrogen and Helium. These gases ultimately led to the formation of the planets and stars.

But then how was the initial burst created? Perhaps another theologian can guess or maybe they already have ;-)

Also, please check my podcast here- Link

Short guide of subatomic particles: quarks and leptons

2015-03-26T14:23:00.000-04:00

As we know from high school science class, atom consists of a nucleus comprised of neutrons and protons and nucleus is surrounded by electrons. But what are protons, neutrons and electrons made of?

Proton is made of two types of elementary particles: one "down quark" and two "up quark". There are six types of quarks. Whereas, neutron is also made of quarks but from two "down quark" and one "up quark". Charge of "up quark" is positive 2/3rd of electron where for "down quark" it's negative 1/3rd of electron. And hence protons are positive and neutrons are neutral.

Quarks can not exist as individual particles like electron does, and always found in combination known as hadrons. Protons and neutrons are hadrons. Quarks, are help together by strong interaction via exchange of gluons. Now hadrons can interact with each other by exchanging mesons. And due to this interaction between hadrons via mesons we have protons and neutrons staying inside of a nucleus.

But what about electrons? Electron in an elementary particle in itself and cannot be broken down further. In fact electron is one of the six elementary particles classified under Leptons. 6 leptons and 6 quarks have 1/2 spin and are Fermions. Fermions refer to particles which follow Fermi-statistics. So matter constituents are leptons and quarks.

There is a one more set of elementary particles which have 1 spin and follow Bose-Einstein statistics. Such particles are known as bosons. There are four types of bosons (higgs, photon, W- and W+). These bosons do not form atom but are force carriers. It is through these bosons that particle interact via electroweak and electromagnetic forces.

One interesting thing to note is that each elementary particle as corresponding anti-particle. Anti-particle have same mass and spin but opposite charge. Attached below is summary of matter constituents forming atom.

(Source of image: http://apchemcyhs.wikispaces.com/Subatomic+Particles)

Why do we feel the heat of the Sun

2015-03-25T15:42:00.003-04:00

We have already discussed in the previous post that a hotter object has atoms with high kinetic energy. If this object is put in contact with a colder object, energetic atoms will start to transfer heat to atoms of colder object and this is phenomenon is known as heat conduction. But, Sun is about 100 million miles away from the earth and yet we still feel it's heat. Space between earth and sun is vacuum with no particles to conduct the heat. So, how is heat conducted 100 million miles away to earth without any heat carriers? This occur through the phenomenon known as "heat radiation".

Sun surface is very hot (about 6000 C) and so atoms of gases (hydrogen and helium) in Sun have very high kinetic energy. Electromagnetic radiation (heat) is emitted whenever an electric charge is accelerated. These energetic atoms have positive charge and negative charge, and constantly bumping into other atoms and thus accelerating and decelerating. So, Sun emits heat in the form of electromagnetic radiation.

Electromagnetic radiation do not require particles to travel and thus can travel through vacuum. This is the reason why we feel heat from the Sun. Couple of things to note is, electromagnetic radiation emission from hot objects consist of wide range of wavelengths (visible light from 400-700 nm) and general distribution of spectrum is shown below:

(Source of image: http://www.spaceflight.esa.int/impress/text/education/Glossary/Glossary_W.html)

So, higher the temperature of body, higher the intensity of energy emitted.

Follow-up questions: how can electromagnetic radiation travel through vacuum and why do accelerated charge emits electromagnetic radiation?

How is heat conducted?

2015-03-24T14:05:00.003-04:00

Let us talk today about how heat conduction occur and why metals are good heat conductors. Heat is energy that can be transferred from hotter to colder body and can be quantified from temperature. But then obvious question is how does this energy transfer takes place? In this discussion, we will only focus on transfer of heat only via conduction and do not take into consideration radiation phenomenon.

At microscopic level, we can quantify heat as motion of atoms. Hotter the body is, more kinetic energy the atoms have (they are shaking vigorously). Now, when you put a hotter body in contact with a colder body, atoms in hotter body which are moving vigorously start to shake the atoms of colder body in contact. This leads to transfer of kinetic energy (vibration of atoms in solids) from hotter body to colder body and thus transfer of heat.

For metals, you also have electrons which are free, so both electrons and atoms will acquire kinetic energy. In fact, both electrons and atoms are responsible for transfer of heat in metals. In case of ceramics and dielectrics, only atoms are responsible for transfer of heat. In solid-state physics, a concept known as phonons is used to describe heat transfer process. Phonons is just a fancy word used to describe collective and in-sync motion of atoms. Because atoms are bound (bonding), you have synchronized motion of atoms.

In next post, let us discuss the phenomenon of radiation which is another way to transfer heat.

Why do metals conduct electricity?

2015-03-23T16:38:00.001-04:00

In the last post, I discussed the difference in bonding between metals and ceramics, and how that is manifested in different properties exhibited by metals and ceramics. Now, let us try to understand why metals actually conduct electricity. The reason again ties down to bonding in metals. Like, I explained here, metals typically exhibit metallic bonding in which all the valence electrons are shared by all the atoms. There is a delocalization of electrons, unlike in covalent and ionic bonds which confine electrons only to neighboring atoms. Now, when an external electric field is applied to metals, these delocalized electrons are easy to move and thus conduct. This simple explanation is basis for Drude Model where Drude actually derives simple quantitative formula for conductivity.

This explanation and thus theory is very elementary and is not be able to give correct quantitative numbers for many other properties (heat capacity and seebeck coefficient) of metals. A more detailed theory known as "band theory" is used to describe why metals conduct electricity whereas ceramics or insulators do not. Description of band theory is not aim of this post. I just wanted to describe electrical conduction in terms of bonding so we can appreciate how bonding can affect properties.

Fundamental difference between metals and ceramics

2015-03-22T20:58:00.002-04:00

Recently, I have decided to change the blog to more science oriented. I have started a podcast (link) where I have decided to share my understanding of various topics in science. I will try to post 3-4 posts a week on topics related to science. So, for this post let's discuss why certain solids are metals and some ceramics. Solids, in general, can be distinguished as metals, ceramics and polymer. I am keeping the focus on difference between metals and ceramics and not going to discuss polymers in this post.

If you checked my last post, matter exist in form of solid due "bonds" which keep atoms together in solid. I discussed three forms of bonds- metallic, covalent and ionic. Metals typically have metallic bonding, which is a delocalized bond where all the valence electrons are shared by each and every atoms. In contrast, covalent and ionic bonds are localized between neighborliness atoms. Atoms in ceramics typically are bound by covalent and ionic bonds. This is the key difference between metals and ceramics and is manifested in difference of properties in metals and ceramics.

In fact, classification of solids as metals and ceramics, in my opinion, is due to different properties. For example, metals conduct electricity whereas ceramics do not. Another example is mechanical properties, metals are ductile and do not crack easily (they can crack at very low temperatures) whereas ceramics are brittle and crack easily. And this distinction in properties is related to difference in bonding types found in metals and ceramics.

In next few posts, I intend to discuss some of the properties of metals and ceramics, and delve into more detailed explanation which again comes down to bonding type between atoms.

Why do matter exist as solids?

2015-03-21T22:25:00.003-04:00

Why do matter exist as solids?

Common forms of matter are solid, liquid and gas. Reason behind existence of matter as any form is governed by interactions between atoms. Electrons surrounding atoms' dictate this interaction. This interaction is what we call as a bond. So, why do atoms interact? Reason for any interaction has to do with decreasing overall energy of the system. There are three possible ways for electrons to interact with electrons of neighboring atoms:

- Atom can share electrons with neighboring atom: known as covalent bond
- One atom gives away its electron to neighboring atom: known as ionic bond
- Atoms share electron with all the whole system, not just surrounding atom: known as metallic bond

Like I said before, driving force for atoms interaction is to decrease their energy. Now, this interaction which is termed as bonds is what keep atoms together and forms solid. Solid will fell apart and form gas if there are no bonds. Now, these bonds determine how atoms stack up- forming structure. I am going to cover this stacking of atoms in next posts. This structure is what determine properties of solids like some are conductive, some not and so on.

Jan Lokpal- difference from govt. proposed bill, some common questions and how will it help us (aam-aadmi)?

2011-08-04T07:08:00.001-04:00

After watching this video(http://www.youtube.com/watch?v=2CHcKlIsvAQ&feature=related), I was inspired to actually understand Lokpal better and writing here what all I could find on internet:

Difference between Government proposed Lokpal Bill and Jan Lokpal Bill proposed by Arvind Kejriwal et al:

Nature of Lokpal: The government wants Lokpal to be an advisory body, which will only forward its enquiry report to the competent authority for action like CVC is merely an advisory body. Central Government Departments seek CVC’s advice on various corruption cases. However, they are free to accept or reject CVC’s advice then why the heck are the making Lokpall? Just rename CVC to Lokpals. Although CBI can register FIR and file case but it has to take permission from government department before registering an FIR, why would departments give permissions when we all know corruption is from top to bottom in most cases? The Jan Lokpal Bill proposes powers to initiate prosecution after completion of investigations.
Policing powers of Lokpal: The government's Lokpal will not have any police powers and it will not be able to register an FIR. Just like CVC cannot direct CBI to initiate enquiries against any officer of the level of Joint Secretary and above on its own. The CBI has to seek the permission of that department, which obviously would not be granted if the senior officers of that department are involved and they could delay the case or see to it that permission would not be granted.The Jan Lokpal proposes police powers and would be able to register FIR, proceed with criminal investigations and launch prosecution.
PM funda: The government's Lokpal won't have powers to investigate any case against PM, which deals with foreign affairs, security and defence. But the Jan Lokpal Bill proposes no such bar on Lokpal's powers. As Arvind Kejriwal says, "if an level B officer in income tax can examine PM's income and impose penalty, why not a Lokpal?" Considering the fact that in scams like Bofors etc PM was also in suspicion, one must also have measures to check his powers!
Jurisdiction of Lokpal: The government's Lokpal will not have jurisdiction over bureaucrats and government officers. The Jan Lokpal will have jurisdiction over politicians, officials and even judges. It also proposes merging the entire vigilance machinery into Lokpal. Talking about Judges, an ordinary person can not file an FIR understandandingly so else everyone will keep on filing against judges. But what is wrong is that only chief justice of India ca allow an FIR against the Judge, who has done only twice in last two decades.

Some questions:

What if some officer in Lokpal becomes corrupt? The entire functioning of Lokpal/ Lokayukta will be completely transparent. Any complaint against any officer of Lokpal shall be investigated and the officer dismissed within two months.
What will happen to existing anti-corruption agencies? CVC, departmental vigilance and anti-corruption branch of CBI will be merged into Lokpal. Lokpal will have complete powers and machinery to independently investigate and prosecute any officer, judge or politician.
Parrallel government or tyranny? Has Supreme Court and Election Comission turned into parrallel government? Then how can an officer: Lokpal- who can only investigate and file case upon complaint and can himself be dismissed by Supreme count, turn into parrallel government?

How will it help a common citizen: If any work of any citizen is not done in prescribed time in any government office, Lokpal will impose financial penalty on guilty officers, which will be given as compensation to the complainant. So, you could approach Lokpal if your ration card or passport or voter card is not being made or if police is not registering your case or any other work is not being done in prescribed time. Lokpal will have to get it done in a month’s time. You could also report any case of corruption to Lokpal like ration being siphoned off, poor quality roads been constructed or panchayat funds being siphoned off. Lokpal will have to complete its investigations in a year, trial will be over in next one year and the guilty will go to jail within two years.

(Sources: http://www.indiaagainstcorruption.org and http://www.box.net/shared/k9bz7pfzj6q6s0us9mil)

Google + invite

2011-07-04T09:17:00.000-04:00

Google had closed the invitation to Google +. Inviting via "adding in circle" is not working also (My friends were unable to invite me via this method). So, here is another method which will lead to invite:

Step 1: simply create a status update (on homepage of Google+ find dialog box like "Share what's new"), e.g. “inviting people” and then pasting the Gmail addresses of friends you want to invite into the “add people” box (Next to +1 and Comment links).

Step 2: They should then go to the url of google + home page via: https://plus.google.com which will ask them to join. Note: invitees may not receive email so go to url instead.
In case you need one, send me your email id on dev@devender.co.cc

Also note that, google+ may not work very well in Mozilla so use chrome especially if you are not able to go beyond join page.

Reality check on oil price hike

2011-06-25T01:32:00.001-04:00

Yesterday, Diesel and LPG's prices were hiked again. This encouraged me to do an analysis for self-satisfaction on whether these price hikes were necessary (rates have been increased 10 times in last one year) or just result of bad administration on PSUs.

Now after talking to some friends who are working in oil industries and internet search.

a) I found that following is processing cost for oil companies:

74% - Cost of the crude oil
11% - Taxes Please note: This has been reduced yesterday significantly! (Ref:Link1 and Link2)
10% - Refining costs
5% - Distribution and marketing (Ref: Link3)

b) Current crude oil cost: Around USD 100/barrel (Ref: Link4)

So, total cost of processing is: USD 135/barrel (from (a) and (b))

1 oil barrel= 42 gallon and hence 159 litres (approx)

Cost per litre of processed oil: USD 0.85= INR 38.2

c) Now, whether processed oil is petrol/diesel/keronses that depends on demand and can vary, Assume it to be:

60 percent petrol
30 percent diesel
10 percent kerosene

d) Current prices/selling prices (in Delhi):

Petrol: 63.37
Diesel: 41.12 (Ref: Link5)
Kerosene: 12.32 (Ref: Link6)

Cost to "aam aadmi"= Selling price= 0.6x63.37 + 0.3x41.12 + 0.1x12.32= 51.59 (from (c) and (d))

Profit/litre on processed oil to companies: 51.59-38.2= INR 13.39!

You kidding me! A profit of 13.39/litre! after hidden taxes like VAT and all it will be still INR 10.00!

If government still shows that companies are in loss and this price rise was only option left, stop fooling us! Improve functionality of PSUs like BPCL, IOCL etc. and prices will come down automatically.

Origin of consciousness? Part-2: Neurons and consciousness

2010-09-04T14:36:00.000-04:00

I have been studying human body and its various components a lot in past couple of months. Recently, while studying components I again came across the question about, “origin of consciousness” which I discussed here. Well, in that post I was more of questioning and trying to draw parallels but now after studying basics of functionality of neurons I believe, I am convinced that consciousness is not really independent or some divine gift.

Neurons are nerve cells and form an important part of our nervous system. Neurons are connected to each other and communicate with electrical signals generated through transfer of ions. These connections effectively act as channels for sensing and determining our behavior like response to any situation. Neurons also store memory (?) and use this memory for taking decisions. If you are familiar with neural logics than you can imagine why they have been named so.

Memory stored in our brain influence our behavior and at times our thinking process. For example, when you go to your old house, where you spent your childhood, then all of sudden your mind will be occupied in recalling the incidents of childhood. One can quote any number of examples. So, here comes the analogy: if neurons control memory, sensing and our response, and our sensing, memory and response affects conscious; then it is possible that consciousness is governed by interaction of neurons. Neurons interact with each other which of course depend upon combination of factors like sensing, physiological state of human etc. These interactions of neurons produce thoughts in brain. Now let us try to prove this with an example, someone present in Africa won’t be thinking of mathematics but why? Because he doesn’t have enough luxury to do so as he needs to make up basic needs, his senses are hammering neurons to get food and his mind will be engaged in thinking new ways of hunting rather than new mathematical theories.

Now, comes the important questions- why then everybody thinks differently? Well, there are 20 billion neurons (?) imagine possible combination of interactions and so many thoughts. You will have one particular combination at a time and hence a particular thought. You might remember that you and your friend were about to say similar thing, why? Because both mind were engaged in similar conditions.

Why are there naxalites?

2010-08-11T08:29:00.000-04:00

I so wanted to write on this issue of Maoists and finally I am trying to pen down my thoughts on this issue. Our perception to many things is due to media. It is the news, debates, pictures shown to us etc, make our perception towards any subject. Maoists are termed as greatest concern for India’s security by our PM Manmohan Singh. Very often, in a week or so, we come across some news of violence in which CRPF Jawans killed, trains derailed and many horrifying pictures. When ‘Maoist’ term come to our mind; we kind of picture terrorists and violence.

I shall quote here some facts about Maoists and their activities:

1. They are spread across 8 states with estimated 2 lakh supporter and 10,000 armed men. They are confined to the tribal belt. This graph shows Maoists affected areas: map1 and this graph shows India’s mineral belt: map2

2. India doesn’t even have a full-scale survey on its mining resources. Illegal mining in India is wide-spread as concluded by Lokayukta reports. They have citied many reports where mining contracts have been granted to relatives of politicians. India has opened mining sector for foreign companies even including 100% FDI for many minerals including Titanium.

3. Maoist is someone who follows ideology of Mao Zedong, who based his teachings on the theories of Marx. One of the theories proposed by Marx was that, “There will always be a class struggle when rich class dominates poor class”. The first graph clearly shows Maoists being spread across the areas which are not so developed and majorly tribal areas.

Now, let us try to correlate these facts, Tribal areas in India are rich in minerals -> there has been wide-spread illegal mining-> though being rich in minerals, people in these areas are poor. So, we can clearly see indications of class struggle in this area where rich (politicians, corporate etc. ) dominating these areas and lower class people still being poor.

Coming back to ‘media’, I have always heard of brutality of Maosits. There have been allegations that media is being paid to portray only violent activites by Maoists and ‘not’ the problems faced by people in that region. I have not seen any media person surveyed that region. Activists like Arundhati Roy's views are never given hype by our media.

So, I believe government of India should take care of problems in tribal belt rather than sending more CRPF Jawans.

Note: I do not support violence and hence Naxalites’ activites. I do not mean to offend anyone and would love to debate about your point of view.