“The distinction between the past, present and future is only a stubbornly persistent illusion” ― Albert Einstein

Universe: A Dream reigning in the veins

Sunday, 21 April 2024

Lyrid meteor shower is happening now




Yes, the Lyrid meteor shower is indeed happening today! The Lyrids are an annual meteor shower that occurs from about April 16 to April 25 each year, with the peak usually around April 22 or 23. The best time to observe them is typically during the predawn hours, when the sky is darkest and the shower's radiant point, the constellation Lyra, is high in the sky. 

These meteors are caused by the Earth passing through the debris left behind by the comet C/1861 G1 Thatcher. If you have clear skies and minimal light pollution, it's a wonderful celestial event to witness. Under a perfectly dark sky, you may be lucky enough to catch a glimpse of 10 to 15 Lyrids per hour.

So why wait!! Just go outside and look upwards. You might just get lucky and witness a heavenly show. 

All the best!!


Prabir Rudra

Share:

Wednesday, 17 April 2024

Fermi Paradox: Where are all the Aliens!??

 



The intriguing idea known as the Fermi Paradox poses the question of why, despite the likelihood that there is extraterrestrial life out there, we have not yet found any proof of these civilizations. The paradox draws attention to the apparent contradiction between the likelihood that extraterrestrial civilizations exist and the paucity of evidence or communication with them. It is named after the Nobel prize-winning physicist Enrico Fermi, who famously raised the question during a discussion about the viability of space travel and the existence of intelligent alien life.

The Fermi Paradox has several proposed solutions and explanations.

The rare earth hypothesis lowers the possibility of the existence of additional intelligent civilizations by suggesting that the conditions required for complex life to arise are exceedingly rare.

The Great Filter Hypothesis postulates that life, whether it be microbiological, complex multicellular, or technological civilizations, may be stuck at some point in its evolutionary process due to an impenetrable barrier.

The theory of technological singularity postulates that sophisticated civilizations will ultimately reach a point at which their technology advances to the point that they are undetectable and uninterested in communicating with other civilizations.

Self-destruction: The theory suggests that civilizations may eventually wipe themselves out through conflict, deterioration of the environment, or other ways before they have an opportunity to colonize other planets or extend into space.







Transcendence: This theory postulates that advanced civilizations may evolve into entities that live outside the realm of human comprehension, such as energy- or digital-based beings, rendering conventional means of communication obsolete.




The Zoo Hypothesis postulates that extraterrestrial civilizations exist and are aware of us, but they have decided not to contact us, either so they may observe us in peace or so they can let us evolve naturally.

Though each of these theories provides a unique viewpoint on why we haven't yet found any evidence of extraterrestrial intelligence, the real reason is still one of the greatest mysteries of science. These days, several studies from various research groups are published annually on the subject of extraterrestrial intelligence. The current exoplanet revolution has bolstered the hypothesis that advanced civilizations might exist outside of Earth.

More instruments are available for researchers to use in this kind of investigation. In April 2018, for instance, NASA's Transiting Exoplanet Survey Satellite (TESS) successfully launched and quickly took over from Kepler, which was retired later that year. Among many other things, the highly anticipated $10 billion James Webb Space Telescope of the agency was launched in December 2021 and is currently searching for possible biosignature chemicals in the atmosphere of neighboring exoplanets. The PLATO (Planetary Transits and Oscillations of Stars) mission of the European Space Agency is scheduled to launch in 2026. Later this decade, three massive ground-based observatories with adequate power to detect exoplanet air are expected to go online: the Extremely Large Telescope, the Giant Magellan Telescope, and the Thirty-Meter Telescope. Furthermore, a very ambitious initiative called Breakthrough Starshot intends to use swarms of small, laser-sailing nanoprobes to conduct up-close studies of Proxima b (The exoplanet Proxima Centauri b, also known as Alpha Centauri Cb, is a member of the larger triple star system Alpha Centauri and is circling the red dwarf star Proxima Centauri, which is the nearest star to the Sun.) and other adjacent worlds. Around 2050, if technology development proceeds as planned, the first of these robotic interplanetary vehicles may take off.






These kinds of missions and tools will aid scientists in expanding their knowledge of astrobiology, which is still in its infancy. For example, we have no idea whether our backyard contains worlds that support life. Since bacteria can endure in harsh conditions, studies conducted on Earth have led to the possibility that microbial life exists on Mars, Europa, Enceladus, and/or Titan, the massive satellite of Saturn. However, none of those planets have been investigated quite well enough for us to be certain.




But the Fermi Paradox is thinking much beyond microorganisms. In order to find a solution, we must ascertain the frequency with which extraterrestrial life emerges as well as the frequency with which it acquires the capacity and inclination to interact with other sentient beings or travel among the stars.

Perhaps the most prevalent life-supporting habitats in the Milky Way galaxy are subterranean waters, like those found on Europa and Enceladus. It appears improbable that organisms evolving in such environments will create spacecraft; in fact, a large number of them might not even be aware that there are other planets to discover. 




Another possibility is alien psychology. Perhaps there are many advanced extraterrestrial civilizations, but the majority don't seem to want to interact with humans or come to Earth. Maybe Earth and its people are just too boring for them to play around with, and they won't until mankind proves intelligent and deserving enough to be accepted into the "galactic club."

Or perhaps the majority of sentient aliens generally remain silent out of fear that communicating with their galactic neighbors will result in their own captivity or destruction. Such possibilities have been mentioned by some researchers, including the late Stephen Hawking, to support their contention that mankind shouldn't actively promote itself.

Then there are the practical challenges associated with the search for sentient aliens. The cosmos is vast and extraordinarily old. Only 200,000 years have passed since the beginning of human history, and only since 1960 have we been searching for potential E.T. radio transmissions. Thus, the likelihood that we coincide with a detectable alien civilization in space and time doesn't appear very high.




Most academics believe that there is most likely no single answer to the Fermi Paradox. The "great silence" that faces us now is probably the result of several circumstances, some of which may have been mentioned above. And it could not be too long until the characteristics of those things become more apparent. 


Prabir Rudra

Share:

Thursday, 11 April 2024

Will Pluto ever regain its status as a planet? Does it matter?

 



The general public was furious. Textbooks needed revision. On August 24, 2006, scientists at the International Astronomical Union (IAU) decided to reclassify Pluto, reducing its status from a planet to a dwarf planet. This decision was widely viewed as a demotion and has had a lasting impact on our understanding of the solar system. 

The whole Pluto controversy is based on the problems with the definition of a "planet." According to the International Astronomical Union, a planet is a celestial entity that 

1)  orbits the sun,    

2)  appears almost spherical    

3)  has largely cleared its orbital vicinity of debris. 

However, opinions on even this collection of measures differ. Despite their massive size, few asteroids have been removed from Earth's and even Jupiter's orbits. Ceres is one example of a small, circular globe that orbits the sun but is not regarded as a planet.


A lot of confusion indeed

The purported downgrade of Pluto from planetary classification presents more significant questions regarding the definition of any object in the solar system, or perhaps in space in general. It demonstrates how science isn't always able to classify objects into neat categories. Because it is not clear how to evaluate the many non-circular objects that round our sun if the definition of a planet is expanded once more. This might potentially cast doubt on the asteroid belt—the vast swath of tiny asteroids that lies between Mars and Jupiter. Or what would happen if a planet were to mysteriously fragment?

Nevertheless, many people are still confused about the controversy surrounding Pluto and the reasons behind its removal from the planetary orbit, even after the argument began nearly 20 years ago. However, the evolution of the solar system from nine planets to eight (at least according to the IAU definition) took a long time and illustrates one of science's greatest assets: the capacity to modify concepts that appear unchanging in the face of new information.


Peculiarity of Pluto

When astronomer Clyde Tombaugh of the Lowell Observatory in Arizona studied photographic plates of the sky on several nights, he saw a tiny dot that floated back and forth against the backdrop of stars. This led to the discovery and classification of Pluto as a planet in 1930 (note the IAU was created in 1919). However, the newest possibility in the solar system was immediately seen as a peculiarity. For 20 of its 248-year journey, it actually approaches the sun closer than Neptune due to its extremely eccentric, or non-circular, orbit. In addition, it is inclined toward the ecliptic, the plane that the other planets in the solar system revolve.

The first object in the Kuiper Belt was identified by scientists in 1992 as 1992 QB1, a small body orbiting beyond Neptune's orbit and out in Pluto's neighborhood. Soon, a large number of these objects were discovered, and they revealed a belt of tiny, frozen worlds like the asteroid belt between Mars and Jupiter. Though first believed to be even larger than Pluto, the faraway body Eris was discovered by astronomers in July 2005, upending Pluto's reign as the ruler of this region.




Confusion all around

The following queries required to be posed to researchers: Did this imply that Eris was a planet as well if Pluto was? What about the smaller things in the asteroid belt or all those other icy objects out in the Kuiper belt? What was the precise threshold for designating a body as a planet? A phrase that had appeared clear-cut and uncomplicated was now revealed to be strangely equivocal.

Following a heated discussion, numerous new definitions for planets were put forth.

Astronomers were no closer to finding a solution a year later, and the problem cast a shadowy pall over the 2006 IAU General Assembly meeting in Prague. Four proposals were put forth throughout the eight days of intense debate that the researchers had to sit through at the meeting. A contentious proposition proposed increasing the number of planets in the solar system to 12, incorporating the largest asteroid, Ceres, and Pluto's moon, Charon. 

By the end of the Prague conference, three new categories for solar system objects were decided upon by the 424 astronomers. Only the planets Mercury through Neptune would be regarded as planets after that. From then on, Pluto and its relatives, which were spherical objects that orbited alongside other objects, were referred regarded as dwarf planets. Small solar system bodies would be the name given to all other objects in orbit around the sun.  

The planet discussion underwent a major sea change as the New Horizon spacecraft flew across Pluto, revealing a world far more active than anyone had previously thought. Big mountains, beaten craters, and evidence of liquid moving across the surface all indicate that the world has experienced significant geological change since it formed. Based solely on this, some, like Stern, have argued that Pluto ought to be classified as a planet because it is a dynamic location that is not so static that the only things that perturb its surface are micrometeorites.



Observations of Charon, the moon of Pluto, reveal a very dynamic planet with a red cap on its pole that seems to change color in response to the gradual seasonal changes that occur so far out in the solar system. Notably, Mercury and Venus, two well-known planets, do not have as many moons as Pluto. (Most asteroids and dwarf planets have moons as well, which further complicates the definition of a planet.)

There are always new classification schemes emerging. As per a suggestion from 2017, a planet is characterized as "a round object in space that's smaller than a star." This would reclassify Pluto as a planet, but it would also reclassify the moon of Earth and many other moons in the solar system, bringing the total number of planets recognized by the scientific community to 110. A year later, Alan Stern, a leader of NASA's New Horizons mission coauthored an editorial piece in The Washington Post with planetary scientist David Grinspoon, claiming that astronomers ought to reevaluate their theories since the IAU's definition was "flawed" and "hurriedly drawn." 




Will Pluto ever regain its planetary status?

So far, these requests have been ignored, and it doesn't appear probable that the IAU will take up the issue again anytime soon. As of now, it is thought that Pluto was misclassified when it was first discovered; it was never on the same footing as the other eight worlds. So Pluto is still not a planet. It was never, in fact. Scientists think that we have misinterpreted it for fifty years. Maybe we are wiser now. Nostalgia for Pluto indeed makes for a weak planet argument, but that's all there is to it. Probably we should move on to reality now.

Does it really matter?

This abundance of planet-forming possibilities suggests that every solar system might be a different ecosystem. Although it is generally true that stars can create planets through the collapse of gas and dust in their surroundings, the specific dynamics involved in planet formation are much more intricate. Are several stars involved, for instance? What is the amount of dust that is available? Is a supernova or a black hole stealing the essential gas and dust that planets require to expand?

All of this suggests that in order to account for the variety of ways that a globe could emerge, our definition of a planet might need to change. Planets might be associated with specific zones or creation conditions. It appears that the only certainty is that planethood and the controversy surrounding Pluto will remain hotly contested for some time to come as data continue to be gathered.

But when modern-day kids (who were not born when Pluto was a planet) raise a question about the necessity of the definition of a planet, it is very difficult to give an answer, and one generally avoids such a situation by saying that it's complicated!!


Prabir Rudra

Share:

Wednesday, 10 April 2024

Theoretical Physicist Peter Higgs, Who Discovered 'God Particle', Dies At 94

 



Peter Higgs, born on May 29, 1929, committed his life to deciphering the secrets of the universe. His 1964 proposal that space is filled with a field that would eventually be called the Higgs field was his groundbreaking contribution to science. Fundamental particles get mass through interactions with this field. A major validation of his pioneering work came in 2012 with the finding of the Higgs boson, the predicted particle associated with the field, at CERN's Large Hadron Collider. Peter Higgs and François Englert split the 2013 Nobel Prize in Physics. The man after whom the particle is named died on Monday, April 8, 2024, at the age of 94.

In order to find the Higgs boson in 2012, the largest and most sophisticated machine in the world had to work for about 50 years. Every other particle is known to acquire mass from an elementary particle, such as an electron, quark, photon, or neutrino, or the Higgs boson. Although its existence was anticipated in the 1960s, it wasn't discovered until 2012 thanks to complex research conducted at the Large Hadron Collider, the largest and priciest machine in the world at the time, which is situated on the French-Swiss border. 




Peter Higgs favored a solitary existence filled with study and introspection. He admitted that he had never used a cell phone, written or received emails, or even viewed the internet. Despite his acute shyness, Higgs had chosen to leave his Edinburgh home on the day of the 2013 Nobel Prize in Physics announcement, confident that his discovery of the Higgs particle the year before would get him the honor. Higgs, who was 82 at the time, continued to stroll the streets, stopped for lunch at a restaurant, and went to an art exhibition in an apparent attempt to avoid the spotlight and the attention that would follow. Eventually, he ran across a former neighbour who delivered the news to him. He said that the discovery of the Higgs particle had ruined his life in a later interview.

The fact that the Higgs boson (mass-giving particle) has been nicknamed the "God particle" is largely responsible for the public's fascination with it. Nobel Prize-winning physicist Leon Lederman coined the phrase when he wrote a book with the same name on the ongoing hunt for the Higgs boson in the 1990s. Lederman was convinced by the publishers to choose the term "God particle," which stuck, instead of calling his book "The Goddamn Particle," which he had intended to use to depict the enigmatic character of the Higgs boson. That phrase is hated by many scientists, primarily because it gave the particle religious undertones in certain quarters.




The Higgs boson is a particle that is intended to explain the mass of all other fundamental particles, which makes it extremely significant. Through the efforts of multiple physicists, it was revealed in the 1950s and 60s that mass is not a fundamental property of matter. Particles such as protons and electrons, despite their apparent similarity, lack mass. Similar to how there is an electric field, magnetic field, or gravitational field, Higgs and other scientists proposed the concept of an all-pervasive field, which they called the Higgs field.

However, Higgs' influence is felt far and wide, cutting across national boundaries and age groups. A tremendously great scientist, and a wonderful person whose imagination and vision have expanded our understanding of the world around us. His groundbreaking work has inspired hundreds of scientists, and for many more generations to come, his legacy will do the same.

Peter Higgs, rest in peace. Your brilliance will endure forever. 


Prabir Rudra

Share:

Sunday, 7 April 2024

If Earth suddenly has the atmosphere of Venus

 



At a distance of 108 million kilometers (67 million miles) from the Sun, Venus is the second closest planet to the Sun in our solar system. So it is expected that the planet of love is a broiling hot inferno.

The conditions on Earth would drastically change if it had the atmosphere of Venus, making it incredibly inhospitable to life as we know it. Once the clear blue sky would now be a thick oppressive canvas of yellow with massive clouds of sulfuric acid. Though they would block out most of the Sun, this would not be enough to mitigate the extremely hot temperatures on the ground. How would that transform the Earth? Will that ring the death bell for all life on Earth? This is what would probably occur:

  • Extreme Heat: Venus has a thick atmosphere primarily made up of carbon dioxide, with some clouds containing sulfuric acid. The runaway greenhouse effect produced by this dense atmosphere traps heat and raises temperatures to extremely high levels. Earth's average temperature would soar to around 460°C (860°F), hot enough to melt lead. 

  • Crushing Pressure: The pressure in Venus's atmosphere is roughly 92 times higher than that of Earth. It is like living approximately 900 meters underwater. Human beings would be crushed and structures would be flattened by this pressure. 


  • Toxic Atmosphere: Venus's atmosphere would be incredibly corrosive due to the sulfuric acid clouds. When they combine with water vapor in the Earth's atmosphere, they would produce acid rain, which is deadly to living things and capable of dissolving most materials. 

  • No Oxygen: In the atmosphere of Venus, oxygen is scarce. Breathing would be impossible for most species, including humans, as a result. Asphyxia and death would result from a shortage of oxygen.


  • No Liquid Water: Any water on the surface of the Earth would either boil away or exist as vapor high in the atmosphere due to the extremely high temperatures and pressure. There wouldn't be any liquid water left on the planet's surface, which is necessary for life as it exists now.


  • No Protection from Radiation: Right now, the atmosphere of Earth acts as a barrier to keep dangerous solar radiation from reaching humans. This shield would be compromised in the presence of an atmosphere like Venus, leaving life on Earth vulnerable to hazardous solar radiation levels. 

But astronomers suggest that things were not always so drastic as it is today in Venus. A long time ago Venus might have had a climate similar to that of Earth. There might even have been oceans of water. But those times are long gone. With time the planet's atmosphere built up an excessive amount of carbon dioxide and other gases trapping heat from the Sun paving the way for a runaway greenhouse effect. Now the planet is basically an apocalyptic wasteland.

If Earth today had a similar atmosphere, all the gardens, trees, and forests would burn out leaving out their blackened skeletons. Birds will fall out of the sky. Animals would gasp their last breaths and even the fishes would bubble out of the sea. Water bodies across the planet will be at their boiling point. With time all the water will boil out and the surface of the Earth will become absolutely dry leaving behind the skeletons of the marine life. With enough time even the things that used to symbolize humanity's achievements would become grotesque sculptures of what they once were. Due to the extreme pressure, the buildings would collapse, and so would the bridges. Roads will develop cracks and become completely undrivable. This will present a devastating image. Overall, if Earth had the atmosphere of Venus, it would become an uninhabitable, hellish world devoid of life as we know it.




The only way to survive these extreme conditions is probably to take shelter underground. Subterranean shelters in the planet's crust will protect us from the extreme heat and pressure. With the right design, these shelters can recreate the favorable atmosphere that we need to stay alive. Geothermal energy can be harnessed and used in these shelters to power them. Another way of survival is to leave Earth and inhabit another planet that has favorable conditions for life. 

Maybe this transformation of Earth as we know it today into a Venus-like planet will not happen overnight as we tried to imagine in the above note, but conditions show that probably we are on course towards reaching such a situation. Global warming, melting of polar caps, pollution, and deforestation are all pointing towards such a catastrophic end to life on Earth.

It's a stark reminder of how delicate and crucial Earth's atmosphere is to sustaining life and preservation of this atmosphere should be our priority.







Prabir Rudra

Share:

Saturday, 30 March 2024

Total Solar Eclipse in April 2024

 



The total solar eclipse that will occur on Monday, April 8, 2024, will cross North America, going over Canada, the United States, and Mexico. When the moon moves between the sun and the Earth and briefly obscures the sun's face, this is known as a total solar eclipse. The term "path of totality" refers to the lunar shadow's trajectory across the surface of Earth. Thirty-one million Americans already reside inside the path of totality, making the celestial marvel accessible to them. The South Pacific Ocean will be the starting point of the total solar eclipse. The Pacific coast of Mexico will witness totality first in continental North America, weather permitting, at approximately 11:07 a.m. PDT.

Following its journey from Mexico, the eclipse will pass across Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire, and Maine before entering the United States in Texas. The complete solar eclipse will also be visible in a few isolated areas of Tennessee and Michigan. After crossing Southern Ontario into Canada, the eclipse will pass over Quebec, New Brunswick, Prince Edward Island, and Cape Breton. At 5:16 p.m. NDT, the eclipse will leave continental North America and cross the Atlantic coast of Newfoundland, Canada.

The total solar eclipse on April 8 is expected to be the largest mass travel event in U.S. history, drawing together eclipse professionals and amateur skywatchers alike.

Various things should be avoided during a solar eclipse. Following is a list of such things:

1) Do not look directly at the sun.

2) Avoid using optical devices.

3) Don't drive wearing eclipse glasses.

4) It is better to avoid travel.

5) Do not drive while trying to watch the eclipse.

6) Use proper eye protection.

7) Don't use optical devices without proper filters.

8) Supervise children while watching the event.


Prabir Rudra


Share:

Thursday, 28 March 2024

The Devil Comet is approaching us




Over the next few days, skywatchers will be able to see more than just the bright planet Mercury and April's total solar eclipse. Comet 12P/Pons-Brooks, sometimes known as the "devil comet," will be visible in the night sky for the next few days and might emerge during the April 8th total solar eclipse. Since Pons-Brooks only completes one orbit around the sun every 71 years, observing it is usually an opportunity that comes only once in a lifetime.

Pons-Brooks is a ball of ice and rock that is 10.5 miles wide. In comparison, it will be twice as large as the Mount Everest. It is currently traveling towards our sun with an extremely elliptical or stretched-out orbit. It features a frozen shell, or nucleus, encircling a core composed of solid ice, gas, and dust. A coma, or a cloud of frozen material, progressively seeps out of the comet's center and covers the nucleus. 

Pons-Brooks is cryovolcanic, unlike most other comets. It frequently erupts when the nucleus's fractures are opened by sun radiation. As a result, frozen cryomagma under extreme pressure erupts into space. The surrounding cloud of frozen particles enlarges and seems brighter than usual when this happens.

For the first time in 69 years, Pons-Brooks erupted violently in July 2023, leaving behind two separate gas and ice trails that resemble a pair of devil horns. It has persisted in erupting rather regularly.


When will it be visible?

Pons-Brooks may become visible to the unaided eye during the next few weeks as it passes through the inner solar system. It will stay that way until April 2 when it moves closer to the sun and disappears from view in the pitch-black night sky. The evenings of 30th and 31st March are considered to be the best time to see the comet as it will be nearest to the Earth at that time. On June 2, when it moves away from the sun, it will be at its closest to Earth. It will be roughly 139.4 million miles away and presents no known hazard to Earth. 

It is expected to become even more active in the upcoming weeks and be visible to the unaided eye with a maximum brightness magnitude of about 4.0, according to SETI Institute postdoctoral scholar Ariel Graykowski. The appearance appears brighter the lower the magnitude. It won't be very noticeable in the sky because "the limit for naked eye objects in dark, moonless skies is around 6 magnitudes," according to Graykowski.


Where should we look?

It is most seen in the early evening in the Northern Hemisphere toward the west-northwest horizon. Pons-Brooks is located low in the northwest sky, close to the Pisces constellation. It should look like a blazing ball of ice, trailed by the forks of its horns.

An hour or so after sunset, the comet should be visible to the unaided eye low in the west. As it approaches the sun, it will become somewhat brighter. You want to find a place where you can see the western horizon unhindered and where there are no city lights. Using binoculars might be a good idea as the comet might be difficult to find without them.

The brightest planet Venus will become visible on one side of the sun as the sky grows darker. Jupiter, the second-brightest planet in the solar system, is located on the other side. Furthermore, you should be able to see Comet Pons-Brooks closer to Jupiter but between Jupiter and the sun if it is sufficiently bright.

Remember this is your only chance to see it because it won't be seen again until 2097. 


Prabir Rudra


Share:

Tuesday, 26 March 2024

Big Bang: The beginning of the Universe





The Big Bang theory is the prevailing cosmological model for the observable universe's earliest known periods and its subsequent large-scale evolution. It proposes that the universe began as a hot, dense state approximately 13.8 billion years ago and has been expanding and cooling ever since.


Here's a brief overview:


1. Initial Singularity: The Big Bang theory proposes that the universe began as a hot, dense point known as a singularity. At this moment, all the matter, energy, space, and time were contained within this infinitesimally small point. As a result, certain qualities became infinite or undefined at the Big Bang, hence the name singularity.


2. Rapid Expansion: Approximately 13.8 billion years ago, the singularity underwent a rapid expansion known as cosmic inflation. This expansion caused the universe to cool down and expand, leading to the formation of subatomic particles and eventually atoms.


3. Formation of Elements: As the universe expanded and cooled, subatomic particles such as protons, neutrons, and electrons combined to form the first hydrogen and helium nuclei. This process, known as Big Bang nucleosynthesis, occurred within the first few minutes after the Big Bang.




4. Formation of Stars and Galaxies: Over millions to billions of years, gravity caused regions of higher density in the early universe to collapse, forming stars and galaxies. Within galaxies, stars formed from clouds of gas and dust, and many stars went on to form planetary systems.


5. Cosmic Microwave Background Radiation (CMB): About 380,000 years after the Big Bang, the universe cooled enough for neutral atoms to form. This event, known as recombination, led to the release of photons that continue to travel through the universe today as the cosmic microwave background radiation. The CMB provides a snapshot of the universe at that early stage.


6. Observable Universe: The expansion of the universe continues to this day. The observable universe, the part of the universe we can see, includes galaxies, clusters of galaxies, and cosmic structures, all moving away from each other due to the ongoing expansion.


The Big Bang theory is supported by a wealth of observational evidence, including the cosmic microwave background radiation, the observed distribution of galaxies, the abundance of light elements, and the large-scale structure of the universe. However, it's important to note that there are still unanswered questions and areas of active research within cosmology, such as the nature of dark matter and dark energy, and the conditions of the universe before the Big Bang. This is probably the reason why various competing theories like the steady state theory, cyclic universe model, multiverse hypothesis, quantum cosmology, etc. find their place in the literature.


Prabir Rudra

Share:

Saturday, 23 March 2024

Emmy Noether: Probably the best female Mathematician in the history




Consider that you are launching a ball into the air. The skill of juggling involves a dance between motion and rest, with the ball's speed decreasing as it rises and increasing as it descends. One of the fundamental ideas of physics is revealed in this dance: conservation laws. Earth, or juggling for that matter, is not the only place where conservation principles apply. These are general laws of physics that hold true in many branches of the subject. However, they aren't always clear-cut. Here's where the woman from Germany enters the scene. Her discovery revealed an incredibly straightforward relationship between these conservation rules and the symmetries of the world.

Emmy Noether, the woman who developed one of the most beautiful theorems in physics. Today (March 23) is her birthday.

Emmy Noether was a German mathematician who made significant contributions to abstract algebra and theoretical physics. She was born on March 23, 1882, in Erlangen, Germany, and died on April 14, 1935, in Bryn Mawr, Pennsylvania, United States.

She developed what is now known as Noether's theorem, which is fundamental in the study of symmetries in physics. This theorem relates symmetries and conservation laws, showing that for every continuous symmetry in a physical system, there is a corresponding conserved quantity.

Despite facing discrimination as a woman in academia during her time, Noether made significant contributions to mathematics and physics. She worked at the University of Göttingen, where she collaborated with prominent mathematicians and physicists such as David Hilbert and Albert Einstein. Her work laid the foundation for modern algebra and had a profound impact on theoretical physics, particularly in the development of quantum mechanics and general relativity.

Noether thought about the issue raised by Hilbert and Einstein, namely that the General Relativity Theory appeared to violate the law of conservation of energy. This led to the development of her well-known theorem, which fundamentally altered the path of physics.

It's likely true that Emmy Noether is the best female mathematician in history. Noether's theorem fundamentally changed our view of the cosmos. Her pioneering work in abstract algebra also revolutionized mathematics.


Contributions

Emmy Noether made several significant contributions to mathematics and theoretical physics during her career. Some of her most notable contributions include:

1. Noether's Theorem: This is arguably her most famous contribution. Noether's theorem states that for every continuous symmetry in a physical system, there is a corresponding conserved quantity. This theorem has profound implications in theoretical physics, particularly in the conservation laws of energy, momentum, and angular momentum.

2.  Abstract Algebra: Noether made significant contributions to abstract algebra, particularly in the development of ring theory and group theory. She introduced the concept of "ideals" in ring theory, which has become a fundamental concept in modern algebra. Her work provided important insights into the structure of algebraic systems.

3. Invariant Theory: Noether worked on invariant theory, a branch of mathematics concerned with properties that remain unchanged under a group of transformations. Her work in this area helped to clarify and extend the understanding of the relationships between symmetry and invariance.

4.  Algebraic Geometry: Noether made contributions to algebraic geometry, particularly in the study of algebraic curves and surfaces. She developed the theory of "Noetherian rings" and made significant advances in understanding the properties of algebraic varieties.

5.  Physics: While primarily a mathematician, Noether's work had a profound impact on theoretical physics. Her theorem has applications in various areas of physics, including classical mechanics, quantum mechanics, and general relativity. She collaborated with notable physicists such as Albert Einstein and David Hilbert, contributing to the development of their theories.

6.  Teaching and Mentorship: Noether was also known for her exceptional teaching skills and mentorship of students. Despite facing discrimination as a woman in academia, she mentored several prominent mathematicians and physicists, inspiring future generations of researchers.

Emmy Noether's contributions to mathematics and theoretical physics have had a lasting impact on these fields, and she is widely regarded as one of the most influential mathematicians of the 20th century. She has left a lasting legacy, with her work continuing to influence research in various fields of science and mathematics.


Prabir Rudra

Share:

Friday, 22 March 2024

Abel Prize for 2024 goes to Michel Talagrand

 



The 2024 Abel Prize has been awarded to Michel Talagrand of the French National Center for Scientific Research (CNRS), Paris, France for his ground-breaking work in functional analysis and probability theory, which has excellent applications in statistics and mathematical physics.

Michel Talagrand is recognized for his contributions to stochastic processes and probability theory. Problems arising in the context of gambling or risk assessment served as the first impetus for the creation of probability theory. An overarching theme throughout Michel Talagrand's seminal discoveries is interacting with and comprehending the stochastic processes surrounding us. It is now evident that in the modern world, a deep comprehension of random events is crucial. For instance, our huge language models and weather forecasts are based on random methods.

Random events are constantly at work in the modern world and have far-reaching implications for everything from condensed matter physics to business logistics. Talagrand's work mostly focuses on comprehending and applying the "Gaussian distribution," which is often referred to as the "Normal distribution" or, because of its form, the "bell curve". The Gaussian distribution governs every aspect of our lives. Weight at birth, grades at school, and retirement ages of athletes are all seemingly random phenomena that nicely fit into the Gaussian distribution.






Specific areas of research

The prize has been awarded for the following three basic areas:

Suprema of stochastic processes: 

The greatest value that can be anticipated from a group of random values is known as the "supremum" of stochastic processes. A stochastic process generates a series of random values. Knowing the expected height of the biggest wave that will hit the beach the following year is helpful if the height of waves that smash onto a beach is determined by a stochastic process.

Concentration of measures: 

It may seem counterintuitive, but when a process relies on a variety of random sources, rather than becoming more complex, the various random components may be able to balance each other out and yield more predictable outcomes. For this, Talagrand has provided accurate quantitative estimations.

Spin glass: 

Leaving abstract probability theory behind, physicists were first surprised to learn that atoms may arrange themselves in a unique form of matter called a "spin glass". Talagrand finished the proof of Giorgio Parisi's work, which won him the Nobel Prize in 2021, by using his understanding of statistics and probability to establish bounds on the behavior of spin glass matter.

Talagrand is a strong problem solver in addition to being an outstanding mathematician. He has significantly advanced our knowledge of random processes, particularly Gaussian processes. His contributions have changed probability theory in several ways. Professor Helge Holden, chair of the Abel Prize Committee, adds, "His proof of the renowned Parisi formula for the free energy of spin glasses is an amazing accomplishment."

Life

Michel Talagrand was born in France in 1952 and graduated from the University of Paris VI with a Ph.D. in mathematics in 1977. He studied for a while at Ohio State University in the United States. He is married and has two sons. He is a member of the French Academy of Sciences and has won various honors and awards. One of the amazing things that he runs on his website is that he challenges mathematicians to solve riddles under the banner "Become rich with my prizes."


Prabir Rudra

Share:

Followers

Subscribe

Enter your email address:

Delivered by FeedBurner

Powered by Blogger.