Physics – Space Age

Stars in The Night Sky- Stars Explained

I am sure that there has been a time in your life when you looked up at the stars in the night sky and thought to yourself. Hmm, I wonder what makes them shine so brightly? There must be some secret behind it. Well, it’s no secret; it’s science! For centuries, stars have been used widely in poetry, essay, children’s rhymes, and lullabies. We have always gazed up at the night sky and tried to identify the constellations. Oftentimes, we are able to identify some prominent stars which are closer to Earth as they usually shine brighter. Let us now delve deeper into the cosmos and understand how these wonderful twinklers get their shine.

How are Stars Born, and what are they made of?

Stars are massive gas giants, not the ones like Jupiter but the ones which are way more massive than Jupiter. Did you know that it requires the mass of 70 Jupiter-sized planets to form the smallest star? 70 Jupiter-sized planets are the smallest amount of material that is enough to trigger nuclear fusion to qualify as a star. This type of star is known as a red dwarf. To understand the principle of star formation, we first need to understand the key concepts of nuclear fusion [1], nebula, and the influence of gases like Hydrogen, Helium, and oxygen.

A nebula is a large accumulation of gas and dust in the fabric of space. Gravity influences this nebula, and the gas and dust begin to shrink and divide into small balls which look like swirling clumps. When each clump becomes ball-shaped, they continue to shrink the material, which begins getting hotter. Once the temperature reaches 10 million degrees centigrade (1 crore), an explosion would occur, thereby resulting in a nuclear fusion. When this fission starts consequently, and at a large scale, a new star is born. There are other ways how a star can be born; one such way is through a supernova explosion (which will be covered in this article), where the death of a massive star gives rise to a new high-density star known as a neutron star.

The Life of a Star

Learning the life of a star would be quite interesting as it delves into various aspects which could broaden the perspective that you have about our universe. It will also help you see our Sun in a new light and understand how its life was and will come to be in the distant future. The life span of a medium-sized star such as our Sun is around 5 billion (500 crores) years. Larger stars would have shorter lifespans; this is because their energy would burn out quicker. Similarly, stars that are smaller than our Sun tend to last longer. Have you ever wondered why stars don’t seem to change at all? A star would look the same to you now just as how you had observed it when you were five years old. This is because your lifespan would be like a second to that of the lifespan of a star.

The Birth of a Star

Not all stars follow the same path; their path would depend on the mass of the star or how much gas was collected and collapsed to form that star. This gas would serve as fuel for the star. In a nebula, when nuclei of an atom collide with enough energy, there would be a large electromagnetic repulsion between them. The strong nuclear force would take over, and the nuclei would fuse, with a small fraction of their mass converting into energy. Only when nuclei collide and fuse into the core of a star will they release enough energy to counteract the gravity crushing inward. The matter that forms a star determines the amount of fuel. With a variety of other factors, the lifetime of a star can be determined.

As we now know that any star begins from a large cloud of gas and dust; this material needs to be at least a few lightyears across. During the earliest era of star formation, this material would exclusively be Hydrogen and Helium. This was what existed in the brief 17 minutes after the big bang nucleosynthesis [2]. Hydrogen and Helium collect due to gravity and push inwards as it contracts. In this process, immense heat is generated, resulting in a nuclear fusion. This entire process is not immediate as it occurs over a few million years. A yellow or red main sequence star will be born in the process of the fusion reaction, and the glow will be the result of this reaction happening in a nearly endless cycle.

The Red Giant Phase

As long as there is hydrogen to fuel the nuclear fusion reaction, the star will continue to shine over a few billion years, depending on the mass of the star. Once the hydrogen fuel begins to deplete, the core of the star will slowly begin shrinking. When the core starts to shrink, it will become much hotter, resulting in the hydrogen fuel burning faster. The fast-burning fuel will result in extra energy released by the reaction, which radiates outwards, resulting in the outer layers of the star being pushed away from the core. This process would result in the star’s outer layers expanding, making it appear like a red giant. When the outer layer cools, the star becomes red. The star will continue to expand until most of the residual fuel is burnt. A star like our Sun will reach this stage of the life cycle around 5 billion years from now. At present, our Sun has already lived 50% of its life. A star will typically stay a red giant for around a billion years.

White Dwarf- The Death of a Star

Yes, even stars die out eventually, but they would have lived a glorious life of 10 billion years (1000 crore) before they die out (This is for a medium-sized star such as our Sun). After all the reserve hydrogen fuel in the star depletes, the core begins to get even smaller and even hotter. This results in a helium flash phase. Wherein the star becomes so hot that it begins fusing heavier helium nuclei into larger nuclei through a process known as triple alpha. This means that the star has a whole new fuel other than the one that it burns for billions of years. This results in the star starting to pulsate as it runs to the final energy fuel. At this point, the star starts to contract and becomes smaller, hotter, and appears blue as most of the Helium has fused into larger nuclei. The core then becomes mostly carbon and oxygen, with a shell of Helium and hydrogen around it.

At this phase, the star has very little material left to burn, and the core will collapse. This results in the star expanding to a red giant once again until its last bursts of energy eject the outer shell. Once the outer layer of the star dissipates, only the core, which is roughly the size of our Earth, will remain. This core will gradually cool due to a lack of fuel to burn as it is not hot enough to fuse carbon or oxygen nuclei. This results in the core contracting further until the star appears to be white, earning the name “white dwarf.” This white dwarf phase would last for 10s or 100 billion years until eventually further cooling and becoming a black dwarf. At present, there are around 8 white dwarf stars discovered among hundred-star systems that are closest to our Sun. There are no known black dwarfs in our universe, as it would take trillions of years for a white dwarf to reach that stage, and our universe is just 13.8 billion years old.

Planetary Nebula- The Circle of Life

Now that we have covered the life cycle of a star let us understand a few things that influence the birth and death of stars. During the red giant phase of a dying star, the shell that ejects from the core is known as a planetary nebula. The name could be misleading as it didn’t appear from a planet; it was because there was confusion during its discovery. A planetary nebula comprises large gas and dust particles, which are nothing but the remnants of a dead star. This gas and dust will become available to join another nebula in the vast universe and form yet another star.

What Happens to Larger Stars?

A star that is over 15 times the mass of our Sun is known as a high-mass star. These stars have much shorter lifespans ranging between 100 million years to even 10 million years. As mentioned before, the larger the star, the shorter its lifespan. High-mass stars usually die out with a bang, which is known as a supernova. Larger stars are formed by larger gas clouds contributing to more mass, which implies more gravity. In these starts, the force pushing inward will be much stronger, resulting in the star being much hotter. This results in faster fusion, generating a great outer pressure to counteract the inward pull of gravity. This type of star is known as the main sequence star, which appears big bright, and blue.

During the last stage of the main sequence star, the fuel runs out, and the core contracts and heats. This results in the star becoming a giant star, as in the case of low and medium-sized stars. However, when the core of a high-mass star begins to compress, it becomes much hotter than a star the size of our Sun. When the core compresses, it forms not only Helium, Carbon, and Oxygen but also Neon and Silicon. These layers are separate and pushed down on the super-hot core, which turns the core into iron. Each layer performs a particular type of fusion until no fuel remains.

A Supernova Explosion Occurs

The core of the star comprises iron nuclei which are so stable that further fusion would release no more energy. When this occurs, gravity wins the fight as there is no longer enough fusion reaction to counteract the force of gravity. All of the outer layers bounce off the core in a single second, resulting in a large massive explosion ejecting all the heavy nuclei and the remaining fuel into outer space. This explosion is what is known as a supernova. Here is a better way to understand it, if you compress an object like a small iron ball or marble using a hydraulic press, the marble ball would eventually explode due to the pressure leaving dust and debris. This is the force of compression at a small level, but the compression that triggers a supernova explosion is much higher.

A supernova explosion is known to be the most violent and energetic phenomenon in the universe. The explosion would be brighter than the entire galaxy that they belong to. It is so bright that its glow would be visible through the naked eye even if you are hundreds of lightyears[3] away from the explosion.

The explosion of a supernova does not leave behind a white dwarf star, unlike low-density stars. If the core of the star before the explosion was between 1.4 or 3 solar masses, the core would not be able to support itself against gravity and will collapse. This collapse will be so powerful that all the electrons will squeeze into protons such that they combine to form neutrons. The shockwave from this event is the supernova. The remnants would be a ball of neutrons bunched up together, which make a large atomic nucleus the size of 20 km in diameter. This resulting core would be so dense that a teaspoon from it would weigh a whopping 10 million (1 crore) tonnes. This core is what is known as a neutron star.

If the core of the resulting neutron star from the supernova is above 3 solar masses, the outward pressure of neutrons pressing against each other (neutron degeneracy pressure) will result in neutrons being crushed together to a single point of infinite density. This single point of density is what is known as a black hole.

Conclusion

Now that we have learned the lifecycle of a star and the birth and death of stars, I will be covering the types of stars in my upcoming articles. Scientists are still on the road to researching different types of stars and are on the verge of discovering new principles that would influence future events in our galaxy. We are still in the infancy stage, and there is a lot more to understand about stars. Now you can gaze at the night sky, knowing how these wonderful twinklers came to life and how they would die. It’s all a circle of life; when one star dies, its remnants (planetary nebula) will influence the birth of another beautiful star.

Glossary

[1] Nuclear fusion– Nuclear fusion occurs when two large nuclei in an atom merge together to form a larger, heavier nucleus. In this process, a lot of energy is released as the overall mass of the resulting nucleus is less than that of the two original nuclei. This leftover mass translates into energy.

[2] Nucleosynthesis- The creation of atomic nuclei at the center of atoms which comprise protons and neutrons. This process occurred within the first few minutes of the big bang.

[3] Lightyear- Distance traveled by light in one year

It’s Rocket Science- Rocket Propulsion Simplified

Jayshree was on her way back from work after a long shift. As she was walking back home, she looked up at the sky and noticed a jet aircraft speeding upward leaving a long stream of smoke in the process. She went into deep thought and wondered how aircraft and rockets are able to produce enough energy that enables them to soar high into the sky and leave the Earth’s atmosphere. She pulled out her smartphone, opened YouTube, and began watching videos explaining rocket propulsion. However, to her dismay, none of those videos seem to explain the concept clearly. That’s when it struck her, what’s better than to ask her boyfriend, Rupesh, who worked at the ISRO space station at Sriharikota as a senior engineer.

When Jayshree reached home, she took a bath and prepared Dosa and Kadai mutton gravy. She finished dinner and decided to call Rupesh and ask him about the question which has been eating her head for the past few hours. She opened Google Keep on her tab to take notes and called her boyfriend.

“Hi babe, how was your day sweetie? I hope all is going well.”

“Everything is going just fine babe, it has been a rough day at work today, as the Chief of Defence visited the ISRO station. We had to keep everything in check and ensure that they were all in order.”

“Oh I see, I hope you are less stressed out now, cause I really need you to explain to me about the science of rocket propulsion.”

“Wow Jayshree, I thought you were not much into the stuff that I do. Anyways, I am all fine and am ready to explain to you, babe.”

Rupesh was quite excited to see that his girlfriend had gained a sudden interest in his line of work and most importantly, was eager to know about rocket propulsion.

What is Rocket Propulsion?

Rupesh cleared his throat and began the lesson, “Just like how you light up a firework during Diwali, rockets work in a similar mechanism to that but with a lot more changes with regards to fuel, combustion method, and other related principles. Let us delve into these concepts step by step.”

“Newton’s third law of motion plays a pivotal role in understanding the principle of rocket propulsion. This states that force exists in pairs. Let’s say an object A exerts force FA on another object which is B. Then B simultaneously exerts a force FB on A, with two forces being equal and opposite. FA= -FB. There are three key factors which contribute to the rocket’s acceleration which are, the rocket’s mass, the exhaust velocity, and the rate at which the exhaust is ejected.”

“In order for a rocket to escape Earth’s gravity, the exhaust velocity needs to be proportional to the gravity of Earth. In other words, the velocity and force exerted by the exhaust need to be powerful enough to counter the gravity of Earth. The force used by the rocket is driven by the fuel which is combusted and forcefully ejected from the exhaust that an equal and opposite reaction occurs.”

“Hmm, I see so that’s how the theory of rocket propulsion plays in. Now can you please elaborate on the components of a rocket?” Asked Jayshree.

Rocket Propellent and its Types

“Jayashree, there are two main types of rocket propellants used in rockets. One is the liquid propellant and the other is a solid propellant. A rocket that is powered by a liquid propellant contains liquid fuel such as liquid oxygen, liquid nitrogen, and an oxidizer. The liquid oxidizer is present on top, with the fuel tank below it, and the pumps, which are below that. The pumps are responsible to carry the fuel and the oxidizer to the combustion chamber, which is right below the exhaust. Since there is no oxygen in outer space, rockets need a liquid oxidizer to ensure combustion as fire cannot burn without oxygen. Liquid propellant-powered rockets are mainly used on space shuttles and unmanned missiles to place satellites in orbit.”

“You have explained it so clearly Rupesh, can you tell me about solid propellant rockets?”

“Of course, Jayshree, you see, solid propellant rockets mainly comprise of two components, which are the solid oxidizer and the solid fuel. The solid fuel oxidizer is a mixture of ammonium nitrate and ammonium dinitramide, which is present in a cylindrical hole in the middle of the rocket. The igniter is used to combust the propellant surface and the hole in the middle acts as the combustion chamber. These rockets comprise a hot exhaust choke which is also found in automobiles. This hot exhaust is choked and the exhaust is expelled from the exit.”

Rupesh continued, “Now that you have learned about the principle of rocket propulsion and the types of rockets, you need to understand what are the factors which influence the rocket’s acceleration Jayashree. You see, the acceleration of the rocket will be greater with the exhaust velocity of the gases being greater than the rocket. Also, the acceleration is greater if the fuel in the rocket burns faster. As the mass of the rocket decreases, the acceleration will be greater, that’s why rockets tend to go faster as they reach the outer layers of the Earth’s atmosphere. This is because half of the fuel would have got burnt, thereby reducing the mass of the rocket.”

Conclusion

“Thanks, Rupesh, you are such a charmer, no wonder I fell for a rocket enthusiast like you. I am so glad that you took the time to explain this, you made complex rocket science seem like a walk in the park.”

“The pleasure is mine babe, I would love for you to visit Sriharikota sometime, I would give you a full-on tour of the place.”

“That would be awesome babe, now that my newfound interest is about science, I would love to visit ISRO soon. Let our next date be amongst large rockets ready to leave the Earth.”

“Absolutely Jayashree, I would love that. And also, always remember, there is always a lot of research going on in the field of rocket science. Did you know that scientists like us are working towards finding different propulsion systems and nuclear-powered rockets? Fossil fuels are going to go extinct in a couple of decades and we need to find new ways to reach outer space.”

Delving Deeper Into Quantum Mechanics With Schrodinger’s Equation

The law of conservation of energy is one of Newton’s primary laws, which states that energy can neither be created nor destroyed. Schrodinger’s equation plays the role of Newton’s laws and conservation of energy by predicting the future behavior of a dynamic system. It clears the air and clarifies the crux of the conservation of energy aspect. The equation is a wave function that predicts the probability of events or outcomes. The detailed outcome is not strictly determined; however, Schrodinger’s equation is widely used to predict the distribution of results.

Who is Schrodinger?

Erwin Schrodinger was an Austrian theoretical physicist who contributed to the wave theory of matter and other aspects of quantum mechanics. For his wide array of contributions, he was awarded the Nobel prize for his contributions in 1933, which was shared by another British physicist.

Schrodinger obtained his doctorate from the University of Vienna in 1906, which helped him to accept a research post at the university’s second physics institute. He served the military in World War one and went to the University of Zurich in 1921. He was such a determined person that he published papers that paved the foundations of quantum wave mechanics well past his retirement. In his work, he described the partial differential equation that has a relationship between the equation of quantum mechanics and mechanics of the atom.

A Quick Brush up

Through the work of Albert Einstein and Max Plank, we have learnt that energy is quantized, and light exhibits wave-particle duality. Quantized energy means that the system can have only certain energies and not a continuum of energies. For instance, only certain speeds at which a car can travel due to its kinetic energy could be having only certain values. Physicist Louis de Broglie extended this duality to include matter, which is that all matter possesses a wavelength. Regardless of it being a tiny electron, a whole body, or a huge star.

An object’s wavelength is inversely proportional to its mass, which means that macroscopic objects have very tiny wavelengths. However, since an electron is so small, its wavelength becomes relevant, which is being around the size of an atom. Therefore, we can conclude that electrons can behave like waves and particles.

Wave-nature of an Electron

An electron can be regarded as a standing wave but not a linear wave. It is a circular standing wave that surrounds the nucleus. This helps us understand why the quantization of the energy of the electron is clear. This is because any circular standing wave can only have an integer number of wavelengths. With the increasing number of wavelengths, more energy will be carried by the wave. An electron in an atom can only have a discreet number set of energy levels.

When an electron strikes a proton of a particular energy, this energy is absorbed, promoting the electron to a higher energy state and increasing the number of wavelengths—contained within the standing wave.

Here, the constructive equivalence of standing waves results in covalent bonding through orbital overlap. When it was realized that electrons exhibit wave behavior, physicists were keen on finding a mathematical model that describes this behavior. In 1925, Erwin Schrodinger achieved this goal with his signature equation.

The Schrodinger’s Equation

Schrodinger’s equation is a differential equation that is hard to decipher and cannot be explained in this article as it contains arithmetic. However, let us look into the conceptual aspect of this equation. Just like how Newton’s second law states that force equals mass into acceleration, the Schrodinger equation is applicable to quantum systems by describing a system’s three-dimensional wave function, which is represented by psi.

H represents the Hamiltonian operator, a set of operations that describe all interactions that impact the system’s state. This refers to the total energy of a particle. Although this calculates the wave function, it doesn’t describe what the wave function is. Physicist Max Born proposed that the wave function has to be interpreted as a probability amplitude. The symbol Ψ tells the probability of an electron found in a particular spot.

In the double-slit experiment, the diffraction pattern illustrates the wave of probability clearly. This pattern illustrates the probability of an electron arriving at any given spot. Bear in mind that the exact location of where an electron will land cannot be predicted; only the probability of arrival at a location can be deciphered. If many electrons arrive, it is apparent that their distribution obeys the wave function.

Schrodinger’s equation computes the wave function deterministically, but the information it contains is probabilistic. This concept of the probabilistic nature of computation was a lot to handle for the scientific community to handle and still continues to be. Just like how sound waves are oscillations in an electromagnetic field, and sound waves are mechanical waves, an electron can be considered as clouds of probability density.

Interpretations of Quantum Mechanics

Schrodinger conceived this equation that helped in interpreting some concepts in quantum mechanics. There were many other physicists who interpreted quantum mechanics, some of which include Copenhagen Interpretation, many-worlds interpretation, Quantum decoherence, and Bohmian Mechanics. These interpretations are different ways of relating the wave function to experimental results and the fundamental beliefs about nature.

Conclusion

The development of quantum mechanics has surely come a long way since Schrodinger’s time, and the recent developments have made a big change in today’s scientific community. Schrodinger’s equation has paved the way for physicists to delve deeper into quantum mechanics and particle physics. Scientists can decipher the interactions of various types of particle matter and compound elements through extensive research.

The Existence Of Parallel Universes

It was a bright sunny day in Springfield Massachusetts, 14-year-old Monica was reading an interesting book about our universe and galaxies. Her father, Richard, an Astrophysicist, was relaxing on his chair after preparing for his pre-requisites for the project.

“Are we living in a vast multiverse, dad?” Monica asked her dad Richard who replied with a calm and composed look, “Well, as far as our current observations go, we live in a vast universe which is within our observable spectrum. But who knows Moni, if there are ground-breaking innovative inventions say something like large, powerful telescopes, we could find a cluster of universes nearby”?

“Oh, does that mean that we could be living alongside numerous universes with several different planets and stars?” Monica shrieked with excitement.

“Not really, Moni, you see, the existence of a parallel universe is not proven and is the product of science fiction, but who knows, the future could hold a lot more that are yet to unfold.”

How Can Parallel Universes Be Discovered?

Monica asked, “Dad is there a way to discover parallel universes? If so, how is it done?”

Richard replied, “Well, in one of my assignments as a sophomore in college, I was assigned to study about the outcome of a probability that could occur. Do you know what I did? I started off by using the alternate and null hypothesis methods. However, that didn’t work well as one of the professors said that you have been looking at it from the wrong perspective. The professor said that in quantum physics, the cause of unpredictable outcomes is vast. For instance, if you take a ball and shoot it through a double slit, you can only know the probabilities of where it will land but cannot predict where exactly it will land. This helped me to come up with various probabilities of the outcome that could occur.”

“Similarly, the many-worlds interpretation that we are now dealing with in the parallel universe concept is closely related to quantum mechanics. All the outcomes could possibly occur, but only one can happen in each universe. It takes an infinite number of parallel universes to account for all possibilities.”

“With the observable universe that began nearly 13.8 billion years ago right after the big bang. Did you know that the big bang itself was not the beginning? Yes, that’s right, for an event like a big bang to occur, there would have been something known as cosmological inflation. Once the inflation ends, the big bang occurs.”

Something Beyond Perhaps?

“Hmm, I see, dad. Can you please elaborate on the concept and the probability of existence? It’s not clear,” said Monica.

“Sure honey, you see, when I explained to you about inflation, I meant that inflation doesn’t end everywhere at once; however, the place where inflation doesn’t end, it continues to inflate, thereby giving rise to more space and more potential big bangs. Once inflation begins, it is nearly impossible to stop inflation from occurring somewhere else. It’s more or less like a chain event. So, as time passes by, more big bangs would continue to occur, giving rise to a large number of independent universes, such as a multiverse.”

“Thanks, dad. Now you have made it clear; I would also like to know whether this is a proven fact or just a theory,” Monica asks.

“Well, these are just ideas drawn by scientists Moni; the problem with these ideas is that there is no way to test the prediction of these parallel universes without any sign of evidence. Scientists can only theorize and postulate various probabilities that may showcase the existence of parallel universes, but they cannot draw a concrete conclusion of the same. If we are stuck in our universe, how could we hope to cross another one?”

“Also, particles don’t simply appear, transform, or disappear. However, they can interact with other matter, energy, or quanta. Here, there is a limitation; these particles can only interact under the laws governed by physics. In all the experiments and observations that scientists have made, there is yet to be a discovery of an interaction that demands the existence of a universe beyond ours.”

What Would a Parallel Universe Be Like?

“I now get the bigger picture, dad, but anyways, let’s say that we discover the existence of another universe; how would that universe be. If so, what would its existence mean to us?” Monica asked excitedly.

Richard looked out of the window for a few seconds and thought for a while; he then turned to Monica and explained. “Well, Monica, this is a really good question, but it looks like you have put me in a tight spot. Anyways, let me try to answer to the best of my ability. Let’s assume that if we were to discover another universe, it would completely change the perspective of our laws, research, the field of cosmology, and even some long-standing physics laws could take the backseat.”

“Yes, that’s right, the laws that govern another universe could be radically different from ours. Maybe, instead of gravity, there could be another force that binds planets. Who knows, even the stars in our neighboring universe could be formed in different ways and comprise elements that are never discovered or heard of. Instead of solar systems, there could be a cluster of stars that form a different network around the galaxy. Time and space would behave in a radically different manner, perhaps even go in reverse. My imagination simply cannot run beyond this, Moni. I hope this answers your question.

“Thanks a lot. Dad, it looks like I can write a cool Sci-Fi story with what you have said. I am looking forward to publishing an article on Parallel universe using these inputs.” Said Monica.

Richard felt satisfied with his daughter’s enthusiasm and said, “That’s my girl, go ahead Moni, I am sure your teacher would be really impressed with your work. Also, I urge you to do your own research and write the article in a unique way that suits your style.”

Tiny Vibrating Strings in the Universe- String Theory Simplified

Gravity has been one of the most pivotal forces that bind planets, stars, and galaxies. Scientists have been keen on understanding the nature of elements through mathematical calculations and analytical methods. Theoretical physicists were unable to make head or tail for several unanswered questions that have baffled them for decades. That’s when Werner Karl Heisenberg, a German theoretical physicist, did extensive research and arrived at string theory. Understanding this theory and deciphering it was like finding a needle in a haystack. The string theory was a single mathematical picture that described all forces and matter. It aimed at addressing various theoretical conundrums with the principle of how gravity works as its fundamental point.

General relativity proposed by Einstein states that gravity was a reaction of large objects, such as planets, towards the curved regions of space. However, theoretical physicists were not convinced as they thought that gravity had to behave like magnetism. This is because even small particles such as fridge magnets stick as they swap photons with the particles on the fridge’s surface. Physicists understood that gravity lacked this description from the perspective of small particles among the four forces in nature. They could predict the appearance of a gravity particle but were unable to calculate what happens when two gravitons smashed together, as mathematical calculations showed infinite energy was packed into a small space. This meant that the math lacked something; this was when string theory found its place.

The string theory draws a new perspective of the standard description of the universe by replacing all matter and force particles with just a single element. These tiny vibrating strings twist and turn in a complex manner. Although this theory broadens the perspective of our universe, it fails to unify certain aspects in physics as scientists continue to debate on its relevance and scope for improvement today.

What is String Theory?

Strings can collide and rebound cleanly without implying physically impossible infinities. Quantum mechanics and probability principles were enough to explain the composition of our universe. However, many problems bothered scientists and prevented them from having a good night’s sleep. Quantum gravity was one of the prominent problems in modern physics; it had to reconcile general relativity with principles of quantum mechanics. There were large gaps in developing a consistent theory of quantum gravity due to several problems in black holes, atomic nuclei, and the early development of the universe during that time. One possible solution, which theorists borrowed from nuclear physicists in the 1970s, is to eliminate the problematic, point-like graviton particles.

String theory is a concrete framework that addresses these pressing questions and others. Point-like particles of particle physics could be modelled as one-dimensional objects known as strings. The behaviour of these strings and the nature of their interaction through space is string theory. There is only one type of string that resembles a small loop or segment of an ordinary string. Picture tying a small string between two poles and striking it. Observe its vibration; through this, you can notice that the string doesn’t vibrate in a particular manner. This is exactly how the string particles interact in the universe.

All elementary particles are viewed as vibrating strings. Over large distances, the mass, charge and other properties of the string determine the vibrational state of the string. One of the vibrational states of the string gives rise to a quantum mechanical particle graviton; it carries the gravitational force. Therefore, string theory nothing but the theory of quantum gravity.

How Does Modern String Theory Connect Mathematical Dots?

As science advanced and new discoveries came to light, the String theory was also the subject of modification. The modern string theory was reformulated in 1988 by John Schwarz, an American theoretical physicist, and Andre Neveu, a French physicist. The new string theory was in a league of its own as it did not have to remain consistent with special relativity and quantum theory. This modified theory was the superstring theory that stated that the world comprises three spatial dimensions and one temporal dimension. For the universe to remain finite, time had to be curved as this would require a second temporal dimension. String theorists envision that some multi-dimensional compactification of space existed at every point in space.

Duality, an abstract mathematical relationship between two situations, looks different but could be translated. Theoretical physicists used analogous dualities that bridge unrelated branches in math, such as geometry and number theory. Each operates differently, but dualities enable mathematicians to translate from one another. String theory has the potential to illuminate the dark web by linking different areas of math; this is still up for debate among scientists. Leading scientists believe that string theory still continues to evolve and remains a very productive field of research with the potential to solve long-standing mathematical equations.

Conclusion

Several scientists still debate the string theory’s future, as it has failed to live up to its promise of uniting gravity and quantum mechanics. However, it has become one of the most useful sets of tools in science. If we understand the nature of dark matter and dark energy, it could give us a better perspective of the universe and maybe make string theory more relevant. This is because understanding the dark matter will open up a pandora’s box that would help scientists analyze different aspects regarding dimensions and vibrating strings. The string theory is just a theory and could also be disproved in the future due to new discoveries in cosmology, astrophysics, quantum mechanics, astronomy, or even overall science.

Meet The Man Who Gave A New Definition To Quantum Physics, Richard Feynman

Passion is the driving force of successful physicists and engineers in this world. It pushes people to explore their inner potential and achieve unimaginable heights in their respective fields through revolutionary breakthroughs. Richard Phillips Feynman was one of the greatest minds the world has ever seen. He was an American theoretical physicist who revolutionized physics through his contributions to quantum electrodynamics, integral formulation of quantum mechanics, and particle physics. His contributions in the field of astrophysics are like the building blocks of scientists to emulate. Come, let us dive into the life of this genius to understand his journey and valuable contributions to this world.

A Natural Born Genius

Richard Feynman was born on 11th May 1918 in New York City, USA, to a humble family that migrated from Minsk in Belarus. He was a late talker as he did not speak until his third birthday but later developed a thick New York accent. He was quite close to his younger sister Joan, who shared the curiosity of the world, just like him. He encouraged Joan to pursue her interests in physics, and this led to her choosing a career in astrophysics. Richard’s father was a salesman brought up in a Jewish family. However, despite his religious upbringing, he always encouraged Richard to ask questions to challenge orthodox thinking and religious beliefs. Richard got his sense of humour from his mother, a fun-loving and caring homemaker known for her prominent funny bone.

Ever since he was a child, Richard had a strong liking towards the way things work and was always in the pursuit of knowledge. As a pre-teen, he maintained an experimental laboratory at home and spent a lot of time repairing radios. In high school, he excelled beyond bounds in physics and would always analyze issues theoretically and arrive at the solution. In high school, he was promoted to a higher math class thanks to his proficiency in solving math equations being way higher than his peers. He was such a gem of a genius that he taught himself trigonometry, advanced algebra, integral calculus, and analytical geometry. He also won the New York University math championship during his last year in high school.

An Impressive Student

Feynman joined the Pi Lambda Phi fraternity when he attended the Massachusetts Institute of Technology. Although he majored in math, he switched to electrical engineering and later on changed to physics, which he thought was more accurate for him. He published forces in molecules in his graduate years, which is now known as the Hellman-Feynman therom. In 1942, he received a PhD from Princeton with his thesis being the principle of least action in quantum mechanics.

Feynman analyzed problems in quantum mechanics and applied the principle of stationary action, which paved a platform for the path integral formulation and Feynman diagrams. His supervisor was astonished by his thesis and exclaimed that no physicist on earth could match Feynman’s command over native materials of theoretical science. Feynman had stellar intellect as he was able to decipher the substance behind equations like a walk in the park. He exhibited an enormous amount of dedication and intelligence, just like how Einstein was at his age.

Assisted in Creating the Atom Bomb

In 1941, he got married to his first wife Arline Greenbaum, who passed away due to tuberculosis in 1945. With world war two raging on and the rising tensions between Japan and the United States after the pearl harbour attack, Feynman was recruited by the government to produce enriched uranium for the atomic bomb in the Manhattan Project. He played a major role in this project and developed a formula with leading scientists to create the fission bomb. After a lot of experiments and trials using a miniature nuclear reactor, his team was able to build the weapon of mass destruction. He was able to provide value addition to the team thanks to his prior experience in working with ballistics problems at Frankford Arsenal in Pennsylvania.

Quantom electrodynamics is the study of how light interacts with matter and how charged particles interact with each other. Feynman was known for his contributions in this field. At Cornell University, Feynman worked on a formulation on electrodynamics which was approved by Freeman Dyson, renowned astrophysics at his prime. He proposed a paper on the theory of positrons, which addressed various equations. He also published papers on the mathematical formulation of applications in quantum electrodynamics in 1951, which paved the way for students at the university to aid in the research.

Contributions to Physics and Engineering

At high school, we all would have studied the superfluity of supercooled liquid helium. If you are lucky enough, your school would have also had experiments on exhibiting this quality of helium, where it showcases a lack of viscosity while flowing. Well, guess what? This concept was discovered by Feynman during his investigation at the California Institute of Technology. He proved this through the quantum mechanical explanation of a Russian physicist’s theory of superfluidity.

Feynman was not just the jack of all trades; he was also the master of all. He proved this through his work on the forces like the strong, weak, electromagnetic, and gravity; he established the investigations of all four interactions. This resulted in his success in quantum electrodynamics and quantum gravity. He was a force to be reckoned with in the field of physics as he established a new idea that aided computer engineers. He knew that there was a relationship between physics and computation; he was one of the first scientists to discover the possibility of quantum computers.

Feynman was a person who loved to explore and never had anything called a comfort zone. He was always on the lookout to learn new things, experiment on different aspects, and learn through questioning and reasoning. In 1980, he began working at Thinking Machines Corporation and helped in building parallel supercomputers. He also considered the idea of constructing quantum computers. He proposed the variational perturbation theory that helped in measuring satellite experiments.

A Dedicated Teacher

Feynman was known for his revolutionary teaching methods, which were unorthodox in nature. He often said that students should be made to think in the most open-minded manner like scientists, and teachers have to constantly kindle their creativity and address their doubts with patience. In his lectures, he would give a holistic view of science in the simplest manner that is easily understandable by even a child. He would emphasize the evolution of life and the nature of knowledge transfer of science to the next generation, which is essential as it would enable humans to achieve things in the realm of science fiction.

Feynman often taught concepts in a very engaging manner. Scientists and students who attended his lectures would say that when he teaches a concept, he explains it in a very personal manner that it feels like he is sharing his life experience. He encouraged students and young scientists to constantly question how everything works and, most importantly, what makes everything work. His lecturers were so engaging that people were glued to their seats like toddlers listening to a wonderful tale of the universe and the romantic interaction between subatomic particles.

Nobel Prize-Winning Physicist

Feynman’s achievements in his lifetime are the equivalent of 10 highly intelligent scientists. His dedication and passion for science was immeasurable, and his contributions in astrophysics and particle physics were unachievable by even renowned scientists. He received the Albert Einstein Award and a gold medal for his contribution to physics in 1954. In 1962, he received the Ernest Orlando Lawrence Award, followed by the Nobel Prize in Physics in 1965. He shared the Nobel prize with two other scientists Schwinger, and Tomonaga, for their contributions in quantum electrodynamics and deep ploughing consequences of elementary particle research. He was also elected as a member of the national academy of sciences but resigned after a few years.

In 1978, tragedy struck Feynman when he faced abdominal pain, which was diagnosed with a rare form of cancer. After multiple surgeries to remove the tumour that was the size of a football, his kidney failed due to duodenal ulcer in 1988. He refused to undergo haemodialysis, which could have prolonged his life for a few months. He passed away on 15th February 1988 at 69. His last words being “I hate to die twice. It’s so boring.”

Conclusion

Richard Feynman was truly one of the most remarkable physicists that the world could ever ask for. A Nobel Prize-winning astrophysics who found his work in the minds of several scientists today, he was one of the most magnificent personalities in science. His sense of humour and elegant personality helped him to hit the jackpot with the ladies. He may have passed away, but his work and ideas continue to tingle the minds of young scientists, students, and science lovers. He has proved that passion and curiosity are what drives people to achieve great heights.