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The 11 Greatest Unanswered Questions of Physics

http://royalphysicist.blogspot.com/2018/01/the-11-greatest-unanswered-questions-of.html

By Sagar Rawal

By Sagar Rawal

Here's a tale of modern physics: Two scientists work at the same university in different fields. One studies huge objects far from Earth. The other is fascinated by the tiny stuff right in front of him. To satisfy their curiosities, one builds the world's most powerful telescope, and the other builds the world's best microscope. As they focus their instruments on ever more distant and ever more minuscule objects, they begin to observe structures and behaviors never before seen—or imagined. They are excited but frustrated because their observations don't fit existing theories.

One day they leave their instruments for a caffeine break and happen to meet in the faculty lounge, where they begin to commiserate about what to make of their observations. Suddenly it becomes clear to both of them that although they seem to be looking at opposite ends of the universe, they are seeing the same phenomena. Like blind men groping a beast, one scientist has grasped its thrashing tail and the other its chomping snout. Comparing notes, they realize it's the same alligator.

This is precisely the situation particle physicists and astronomers find themselves in today. Physicists, using linear and circular particle accelerators as their high-resolution "microscopes," study pieces of atoms so small they can't be seen. Astronomers, using a dozen or so new supersize telescopes, also study the same tiny particles, but theirs are waiting for them in space. This strange collision of information means that the holy grail of particle physics—understanding the unification of all four forces of nature (electromagnetism, weak force, strong force, and gravity)—will be achieved in part by astronomers.

The implications are exciting to scientists because bizarre marriages of unrelated phenomena have created leaps of understanding in the past. Pythagoras, for example, set science spinning when he proved that abstract mathematics could be applied to the real world. A similar leap occurred when Newton discovered that the motions of planets and falling apples are both due to gravity. Maxwell created a new era of physics when he unified magnetism and electricity. Einstein, the greatest unifier of them all, wove together matter, energy, space, and time.

But nobody has woven together the tiny world of quantum mechanics and the big world we see when we look through a telescope. As these come together, physicists realize they are getting very close to a single "theory of everything" that accounts for the fundamental workings of nature, the long-sought unified field theory.

About two years ago, after a presentation by the National Research Council's board on physics and astronomy that showed the converging agendas of the two fields, NASA administrator Daniel Goldin suggested a special report that would detail how much astronomers and physicists could benefit from one another's insight. Recently, the council's committee on the physics of the universe released that report. It details 11 profound questions, some of which may be answered within a decade. If so, science is likely to make one of its greatest leaps in history.

But first, what we don't know.

Question 1

What is dark matter?
All the ordinary matter we can find accounts for only about 4 percent of the universe. We know this by calculating how much mass would be needed to hold galaxies together and cause them to move about the way they do when they gather in large clusters. Another way to weigh the unseen matter is to look at how gravity bends the light from distant objects. Every measure tells astronomers that most of the universe is invisible.

It's tempting to say that the universe must be full of dark clouds of dust or dead stars and be done with it, but there are persuasive arguments that this is not the case. First, although there are ways to spot even the darkest forms of matter, almost every attempt to find missing clouds and stars has failed. Second, and more convincing, cosmologists can make very precise calculations of the nuclear reactions that occurred right after the Big Bang and compare the expected results with the actual composition of the universe. Those calculations show that the total amount of ordinary matter, composed of familiar protons and neutrons, is much less than the total mass of the universe. Whatever the rest is, it isn't like the stuff of which we're made.

The quest to find the missing universe is one of the key efforts that has brought cosmologists and particle physicists together. The leading dark-matter candidates are neutrinos or two other kinds of particles: neutralinos and axions, predicted by some physics theories but never detected. All three of these particles are thought to be electrically neutral, thus unable to absorb or reflect light, yet stable enough to have survived from the earliest moments after the Big Bang.

Question 2

What is dark energy?
Two recent discoveries from cosmology prove that ordinary matter and dark matter are still not enough to explain the structure of the universe. There's a third component out there, and it's not matter but some form of dark energy.

The first line of evidence for this mystery component comes from measurements of the geometry of the universe. Einstein theorized that all matter alters the shape of space and time around it. Therefore, the overall shape of the universe is governed by the total mass and energy within it. Recent studies of radiation left over from the Big Bang show that the universe has the simplest shape—it's flat. That, in turn, reveals the total mass density of the universe. But after adding up all the potential sources of dark matter and ordinary matter, astronomers still come up two-thirds short.

The second line of evidence suggests that the mystery component must be energy. Observations of distant supernovas show that the rate of expansion of the universe isn't slowing as scientists had once assumed; in fact, the pace of the expansion is increasing. This cosmic acceleration is difficult to explain unless a pervasive repulsive force constantly pushes outward on the fabric of space and time.

Why dark energy produces a repulsive force field is a bit complicated. Quantum theory says virtual particles can pop into existence for the briefest of moments before returning to nothingness. That means the vacuum of space is not a true void. Rather, space is filled with low-grade energy created when virtual particles and their antimatter partners momentarily pop into and out of existence, leaving behind a very small field called vacuum energy.

That energy should produce a kind of negative pressure, or repulsion, thereby explaining why the universe's expansion is accelerating. Consider a simple analogy: If you pull back on a sealed plunger in an empty, airtight vessel, you'll create a near vacuum. At first, the plunger will offer little resistance, but the farther you pull, the greater the vacuum and the more the plunger will pull back against you. Although vacuum energy in outer space was pumped into it by the weird rules of quantum mechanics, not by someone pulling on a plunger, this example illustrates how repulsion can be created by a negative pressure.

Question 3

How were the heavy elements from iron to uranium made?
Both dark matter and possibly dark energy originate from the earliest days of the universe, when light elements such as helium and lithium arose. Heavier elements formed later inside stars, where nuclear reactions jammed protons and neutrons together to make new atomic nuclei. For instance, four hydrogen nuclei (one proton each) fuse through a series of reactions into a helium nucleus (two protons and two neutrons). That's what happens in our sun, and it produces the energy that warms Earth.

But when fusion creates elements that are heavier than iron, it requires an excess of neutrons. Therefore, astronomers assume that heavier atoms are minted in supernova explosions, where there is a ready supply of neutrons, although the specifics of how this happens are unknown. More recently, some scientists have speculated that at least some of the heaviest elements, such as gold and lead, are formed in even more powerful blasts that occur when two neutron stars—tiny, burned-out stellar corpses—collide and collapse into a black hole.

QUESTION #4: The number of neutrinos in the universe is almost uncountable. If each one has even the tiniest mass, represented here by the ball on the right, which weighs just a bit more than the zero-mass ball on the left, this weight could account for a lot of the universe's missing dark matter.

Dan Winters & Gary Tanhauser

Question 4

Do neutrinos have mass?

Nuclear reactions such as those that create heavy elements also create vast numbers of ghostly subatomic bits known as neutrinos. These belong to a group of particles called leptons, such as the familiar electron and the muon and tau particles. Because neutrinos barely interact with ordinary matter, they can allow a direct look into the heart of a star. This works only if we are able to capture and study them, something physicists are just now learning to do.

Not long ago, physicists thought neutrinos were massless, but recent advances indicate that these particles may have a small mass. Any such evidence would also help validate theories that seek to find a common description of three of the four natural forces—electromagnetism, strong force, and weak force. Even a tiny bit of heft would add up because a staggering number of neutrinos are left over from the Big Bang.

Question 5

Where do ultrahigh-energy particles come from?
The most energetic particles that strike us from space, which include neutrinos as well as gamma-ray photons and various other bits of subatomic shrapnel, are called cosmic rays. They bombard Earth all the time; a few are zipping through you as you read this article. Cosmic rays are sometimes so energetic, they must be born in cosmic accelerators fueled by cataclysms of staggering proportions. Scientists suspect some sources: the Big Bang itself, shock waves from supernovas collapsing into black holes, and matter accelerated as it is sucked into massive black holes at the centers of galaxies. Knowing where these particles originate and how they attain such colossal energies will help us understand how these violent objects operate.

 
Question 6

Is a new theory of light and matter needed to explain what happens at very high energies and temperatures?
All of that violence cited in question 5 leaves a visible trail of radiation, especially in the form of gamma rays—the extremely energetic cousins of ordinary light. Astronomers have known for three decades that brilliant flashes of these rays, called gamma-ray bursts, arrive daily from random directions in the sky. Recently astronomers have pinned down the location of the bursts and tentatively identified them as massive supernova explosions and neutron stars colliding both with themselves and black holes. But even now nobody knows much about what goes on when so much energy is flying around. Matter grows so hot that it interacts with radiation in unfamiliar ways, and photons of radiation can crash into each other and create new matter. The distinction between matter and energy grows blurry. Throw in the added factor of magnetism, and physicists can make only rough guesses about what happens in these hellish settings. Perhaps current theories simply aren't adequate to explain them.

QUESTION #7: Add a little heat, and molecules can be easily transformed from solids into liquids and then gases. But what happens at extreme temperatures? Does matter break down into a soup of subatomic particles—called a quark-gluon plasma—and then into energy?

Dan Winters & Gary Tanhauser

Question 7

Are there new states of matter at ultrahigh temperatures and densities?
Under extreme energetic conditions, matter undergoes a series of transitions, and atoms break down into their smallest constituent parts. Those parts are elementary particles called quarks and leptons, which as far as we know cannot be subdivided into smaller parts. Quarks are extremely sociable and are never observed in nature alone. Rather, they combine with other quarks to form protons and neutrons (three quarks per proton) that further combine with leptons (such as electrons) to form whole atoms. The hydrogen atom, for example, is made up of an electron orbiting a single proton. Atoms, in turn, bind to other atoms to form molecules, such as H2O. As temperatures increase, molecules transform from a solid such as ice, to a liquid such as water, to a gas such as steam.

That's all predictable, known science, but at temperatures and densities billions of times greater than those on Earth, it's possible that the elementary parts of atoms may come completely unglued from one another, forming a plasma of quarks and the energy that binds quarks together. Physicists are trying to create this state of matter, a quark-gluon plasma, at a particle collider on Long Island. At still higher temperatures and pressures, far beyond those scientists can create in a laboratory, the plasma may transmute into a new form of matter or energy. Such phase transitions may reveal new forces of nature.

These new forces would be added to the three forces that are already known to regulate the behavior of quarks. The so-called strong force is the primary agent that binds these particles together. The second atomic force, called the weak force, can transform one type of quark into another (there are six different "flavors" of quark—up, down, charm, strange, top, and bottom). The final atomic force, electromagnetism, binds electrically charged particles such as protons and electrons together. As its name implies, the strong force is by far the most muscular of the three, more than 100 times as powerful as electromagnetism and 10,000 times stronger than the weak force. Particle physicists suspect the three forces are different manifestations of a single energy field in much the same way that electricity and magnetism are different facets of an electromagnetic field. In fact, physicists have already shown the underlying unity between electromagnetism and the weak force.

Some unified field theories suggest that in the ultrahot primordial universe just after the Big Bang, the strong, weak, electromagnetic, and other forces were one, then unraveled as the cosmos expanded and cooled. The possibility that a unification of forces occurred in the newborn universe is a prime reason particle physicists are taking such a keen interest in astronomy and why astronomers are turning to particle physics for clues about how these forces may have played a role in the birth of the universe. For unification of forces to occur, there must be a new class of supermassive particles called gauge bosons. If they exist, they will allow quarks to change into other particles, causing the protons that lie at the heart of every atom to decay. And if physicists prove protons can decay, the finding will verify the existence of new forces.

That raises the next question.

QUESTION #8: All the atoms in the universe are built around an essential particle—the proton. But unified field theory predicts that time may eventually run out for protons, and they could decay into a spray of subparticles.

Dan Winters & Gary Tanhauser

Question 8

Are protons unstable?
In case you're worried that the protons you're made of will disintegrate, transforming you into a puddle of elementary particles and free energy, don't sweat it. Various observations and experiments show that protons must be stable for at least a billion trillion trillion years. However, many physicists believe that if the three atomic forces are really just different manifestations of a single unified field, the alchemical, supermassive bosons described above will materialize out of quarks every now and then, causing quarks, and the protons they compose, to degenerate.

At first glance, you'd be forgiven for thinking these physicists had experienced some sort of mental decay on the grounds that tiny quarks are unlikely to give birth to behemoth bosons weighing more than 10,000,000,000,000,000 times themselves. But there's something called the Heisenberg uncertainty principle, which states that you can never know both the momentum and the position of a particle at the same time, and it indirectly allows for such an outrageous proposition. Therefore, it's possible for a massive boson to pop out of a quark making up a proton for a very short time and cause that proton to decay.

Question 9

What is gravity?
Next there's the matter of gravity, the odd force out when it comes to small particles and the energy that holds them together. When Einstein improved on Newton's theory, he extended the concept of gravity by taking into account both extremely large gravitational fields and objects moving at velocities close to the speed of light. These extensions lead to the famous concepts of relativity and space-time. But Einstein's theories do not pay any attention to quantum mechanics, the realm of the extremely small, because gravitational forces are negligible at small scales, and discrete packets of gravity, unlike discrete packets of energy that hold atoms together, have never been experimentally observed.

Nonetheless, there are extreme conditions in nature in which gravity is compelled to get up close and personal with the small stuff. For example, near the heart of a black hole, where huge amounts of matter are squeezed into quantum spaces, gravitational forces become very powerful at tiny distances. The same must have been true in the dense primordial universe around the time of the Big Bang.

Physicist Stephen Hawking identified a specific problem about black holes that requires a bridging of quantum mechanics and gravity before we can have a unified theory of anything. According to Hawking, the assertion that nothing, even light, can escape from a black hole is not strictly true. Weak thermal energy does radiate from around black holes. Hawking theorized that this energy is born when particle-antiparticle pairs materialize from the vacuum in the vicinity of a black hole. Before the matter-antimatter particles can recombine and annihilate each other, one that may be slightly closer to the black hole will be sucked in, while the other that is slightly farther away escapes as heat. This release does not connect in any obvious way to the states of matter and energy that were earlier sucked into that black hole and therefore violates a law of quantum physics stipulating that all events must be traceable to previous events. New theories may be needed to explain this problem.

Question 10

Are there additional dimensions?
Wondering about the real nature of gravity leads eventually to wondering whether there are more than the four dimensions we can easily observe. To get to that place, we might first wonder if nature is, in fact, schizophrenic: Should we accept that there are two kinds of forces that operate over two different scales—gravity for big scales like galaxies, the other three forces for the tiny world of atoms? Poppycock, say unified theory proponents—there must be a way to connect the three atomic-scale forces with gravity. Maybe, but it won't be easy. In the first place, gravity is odd. Einstein's general theory of relativity says gravity isn't so much a force as it is an inherent property of space and time. Accordingly, Earth orbits the sun not because it is attracted by gravity but because it has been caught in a big dimple in space-time caused by the sun and spins around inside this dimple like a fast-moving marble caught in a large bowl. Second, gravity, as far as we have been able to detect, is a continuous phenomenon, whereas all the other forces of nature come in discrete packets.

All this leads us to the string theorists and their explanation for gravity, which includes other dimensions. The original string-theory model of the universe combines gravity with the other three forces in a complex 11-dimensional world. In that world—our world—seven of the dimensions are wrapped up on themselves in unimaginably small regions that escape our notice. One way to get your mind around these extra dimensions is to visualize a single strand of a spiderweb. To the naked eye, the filament appears to be one dimensional, but at high magnification it resolves into an object with considerable width, breadth, and depth. String theorists argue that we can't see extra dimensions because we lack instruments powerful enough to resolve them.

We may never see these extra dimensions directly, but we may be able to detect evidence of their existence with the instruments of astronomers and particle physicists.

Question 11

How did the universe begin?
If all four forces of nature are really a single force that takes on different complexions at temperatures below several million degrees, then the unimaginably hot and dense universe that existed at the Big Bang must have been a place where distinctions between gravity, strong force, particles, and antiparticles had no meaning. Einstein's theories of matter and space-time, which depend upon more familiar benchmarks, cannot explain what caused the hot primordial pinpoint of the universe to inflate into the universe we see today. We don't even know why the universe is full of matter. According to current physics ideas, energy in the early universe should have produced an equal mix of matter and antimatter, which would later annihilate each other. Some mysterious and very helpful mechanism tipped the scales in favor of matter, leaving enough to produce galaxies full of stars.

Fortunately, the primordial universe left behind a few clues. One is the cosmic microwave background radiation, the afterglow of the Big Bang. For several decades now, that weak radiation measured the same wherever astronomers looked at the edges of the universe. Astronomers believed such uniformity meant that the Big Bang commenced with an inflation of space-time that unfolded faster than the speed of light.

More recent careful observation, however, shows that the cosmic background radiation is not perfectly uniform. There are minuscule variations from one small patch of space to another that are randomly distributed. Could random quantum fluctuations in the density of the early universe have left this fingerprint? Very possibly, says Michael Turner, chairman of the astrophysics department at the University of Chicago and chairman of the committee that came up with these 11 questions. Turner and many other cosmologists now believe the lumps of the universe—vast stretches of void punctuated by galaxies and galactic clusters—are probably vastly magnified versions of quantum fluctuations of the original, subatomic-size universe.

And that is just the sort of marriage of the infinite and the infinitesimal that has particle physicists cozying up to astronomers these days, and why all 11 of these mysteries might soon be explained by one idea.

---

How Did We Get Here?

Astronomers cannot see all the way back in time to the origin of the universe, but by drawing on lots of clues and theory, they can imagine how everything began.

Their model starts with the entire universe as a very hot dot, much smaller than the diameter of an atom. The dot began to expand faster than the speed of light, an expansion called the Big Bang. Cosmologists are still arguing about the exact mechanism that may have set this event in motion. From there on out, however, they are in remarkable agreement about what happened. As the baby universe expanded, it cooled the various forms of matter and antimatter it contained, such as quarks and leptons, along with their antimatter twins, antiquarks and antileptons. These particles promptly smashed into and annihilated one another, leaving behind a small residue of matter and a lot of energy. The universe continued to cool down until the few quarks that survived could latch together into protons and neutrons, which in turn formed the nuclei of hydrogen, helium, deuterium, and lithium. For 300,000 years, this soup stayed too hot for electrons to bind to the nuclei and form complete atoms. But once temperatures dropped enough, the same hydrogen, helium, deuterium, and lithium atoms that are around today formed, ready to start a long journey into becoming dust, planets, stars, galaxies, and lawyers.

Gravity—the weakest of the forces but the only one that acts cumulatively across long distances—gradually took control, gathering gas and dust into massive globs that collapsed in on themselves until fusion reactions were ignited and the first stars were born. At much larger scales, gravity pulled together huge regions of denser-than-average gas. These evolved into clusters of galaxies, each one brimming with billions of stars.

Over the eons fusion reactions inside stars transformed hydrogen and helium into other atomic nuclei, including carbon, the basis for all life on Earth.

The most massive stars sometimes exploded in energetic supernovas that produced even heavier elements, up to and including iron. Where the heaviest elements, such as uranium and lead, came from still remains something of a mystery.
—E. H.

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8 Ways to Win the Nobel Prize in Physics

 http://royalphysicist.blogspot.com/2018/01/8-ways-to-win-nobel-prize-in-physics.html

By Sagar Rawal

It’s 5 a.m. and you’re sitting by the phone, hoping for that “magic call” from Stockholm that bears the news you’ve waited so long for: You’ve won the Nobel Prize in Physics! Whom will you tell first? How will you celebrate? And what color Bugatti should you buy with your prize money?1 But while you’re mentally debating the relative merits of Obsidian Black and Italian Red, you realize that the sun has come up and the phone still sits silent: You’ve been passed over once again. How can you turn things around in 2013? With the announcement of the 2013 Nobel Prize in Physics expected to come on Tuesday, October 8, we consulted with winners and watchers of the Nobel Prize to prepare this helpful guide to nabbing your very own physics Nobel.

Albert Einstein during a lecture in Vienna in 1921, the year of his Nobel Prize. Image credit: Ferdinand Schmutzer, via Wikimedia

1. Think big: What kind of discovery is most likely to earn Nobel laurels? Prize-winning work “runs the gamut” from basic to applied science and from lone-wolf labor to cast-of-thousands collaborations, says Adam Riess, who, along with Saul Perlmutter and Brian Schmidt, received the award in 2011 for the discovery of the accelerating expansion of the universe. Says Riess: “I think the key is its importance must be fundamental, generally involving new physics.”
2. Do an experiment: Physicists are often divided into two camps: theorists, who need nothing more than paper, pencil, and their prodigious brains to do their work, and experimentalists, who toil and tinker with arcane equipment in their attempts to prove (or disprove) the ideas thought up by the theorists. So, which group bags more Nobels? In The Nobel Prize: A History of Genius, Controversy, and Prestige, science historian Burton Feldman lands firmly on the side of experiment. Tallying up the winners from 1901 through 1999, he finds that experimentalists scooped up 87 awards while the theorists made do with a measly 51. Even Einstein, despite a bushel of nominations, was rejected year after year for the Nobel because his relativity theories were just that—theories. (He eventually won the 1921 prize, for his work on the photoelectric effect.) Experimentalists have continued to dominate in the last decade, with a few notable exceptions, like the 2004 award, which went to David Gross, David Politzer and Frank Wilczek for developments in the theory of the strong force, one of the fundamental forces of physics.
3. Keep it in the family: Marie Curie shared the prize with her husband, Pierre Curie, and five father-son pairs have won the award (though only William and Lawrence Bragg won it in the same year for work done collaboratively). As David Kaiser, a physicist and science historian at MIT, puts it: To win the award, “one should select one’s parents carefully.”
4. You can’t choose your family, but you can choose your thesis advisor: “As the great sociologist of science Harriet Zuckerman demonstrated years ago, among all the Nobel laureates who conducted their prize-winning research in the United States (at least up through 1972), more than half had been mentored early in their careers by other Nobel laureates,” reports Kaiser. “The proportion was highest—nearly 2/3—among Nobel Prize-winners in physics.”
5. Be a man—and be eligible for the AARP: Of the 193 winners of the Nobel Prize in Physics, only two (Marie Curie and Maria Goeppert-Mayer) were female. Average age: 55.
6. Get lucky: “They key to winning the Prize, I believe, is to be extremely lucky,” says Riess. Of course, as any fortune cookie can tell you, good luck alone isn’t enough: it has to be combined with the day-in, day-out hard work that often obscures the serendipitous path to the breakthrough. But it is possible to “court serendipity” by being open to surprising and unexpected new findings. The Institute of Physics has compiled a list of just such lucky breaks. There’s Jocelyn Bell’s “accidental” discovery of pulsars—radio signals so uncannily regular that she momentarily thought they might be beacons from an alien civilization. (They weren’t. Incidentally, Bell didn’t get the prize; it went to her supervisor, Anthony Hewish. See #5, above.) And then there’s the first detection of the radio buzz we now know as the cosmic microwave background radiation, which future Nobel laureates Arno Penzias and Robert Wilson chalked up to pigeon droppings before they realized it was actually an electromagnetic echo of the Big Bang.
7. Be patient: The Nobel committee is not much for instant gratification. Though some Nobel prizes come quick on the heels of the work that they honor—the 2010 award, for instance, went to Andre Geim and Konstantin Novoselov for their work on graphene, just six years after the material was discovered—the prize more often comes a decade or two (or five) after the discoveries are first made. Subramanyan Chandrasekhar, for one, had to wait more than 40 years, and 53 years passed before Ernst Ruska was honored for building the first electron microscope that could out-magnify a traditional optical scope.
8. Be prepared for life after Nobel: “What happens now to the rest of my life? What comes after this?” said Tsung-Dao Lee, who received the physics prize in 1957, when he was just 31. Indeed, some laureates, particularly those who receive the award early in their careers, founder after making the trip to Stockholm. As Mitchell Wilson put it in a 1969 essay in The Atlantic, “If, before winning the prize, the man has received very few, if any, of the signs of the scientific world’s recognition of the worth of his work, the sudden rise to stardom can completely distort the pattern of the rest of his life.” But Nobel laureate Frank Wilczek, asked to weigh in on how to up your Nobel odds, has a more spirited outlook: “I’m more confident giving this tip, about what to do immediately after winning a Nobel Prize. And that is, you should take some dancing lessons. They’ll pay off handsomely during the festivities.”

1Just kidding; I’m not aware of any Nobel laureates who plunked down their prize money on a supercar. Nobel winners typically spend the purse on serious and practical things, like charitable donations or their children’s college fund. 

Some of Questions, I collected So Far for you to look for and wonder why does this happen and who know you could be the Next Einstein from Nepal ( that sounds cool, right?? )

Question 1

What is dark matter?

Question 2

What is dark energy?

Question 3

How were the heavy elements from iron to uranium made?

Question 4

Do neutrinos have mass?

Question 5

Where do ultrahigh-energy particles come from?

Question 6

Is a new theory of light and matter needed to explain what happens at very high energies and temperatures?

Question 7

Are there new states of matter at ultrahigh temperatures and densities?

Question 8

Are protons unstable?

Question 9

What is gravity?

Question 10

>Are there additional dimensions?

Question 11

How did the universe begin?

Question 12

How Did We Get Here?

Question 13

Can we get energy from nothing?

Question 14

Why does space have three dimensions?

Question 15

Why do we move forward in time?

Question 16

Where does quantum weirdness end?

Question 17

Is the universe infinite or just very big?

OR Simply you can

Unify the four fundamental forces, unite general relativity and quantum mechanics in a way that can be empirically verified within a short Framework of time and come up with a way of building the Infinite probability drive from Hichhiker’s guide.

Go Through The Below link to explore more Details and where we stand now from solving the puzzle of physics of above mentioned Questions

The 11 Greatest Unanswered Questions of Physics

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Why an Old Theory of Everything Is Gaining New Life

Twenty-five particles and four forces. That description — the Standard Model of particle physics — constitutes physicists’ best current explanation for everything. It’s neat and it’s simple, but no one is entirely happy with it. What irritates physicists most is that one of the forces — gravity — sticks out like a sore thumb on a four-fingered hand. Gravity is different.

Unlike the electromagnetic force and the strong and weak nuclear forces, gravity is not a quantum theory. This isn’t only aesthetically unpleasing, it’s also a mathematical headache. We know that particles have both quantum properties and gravitational fields, so the gravitational field should have quantum properties like the particles that cause it. But a theory of quantum gravity has been hard to come by.

In the 1960s, Richard Feynman and Bryce DeWitt set out to quantize gravity using the same techniques that had successfully transformed electromagnetism into the quantum theory called quantum electrodynamics. Unfortunately, when applied to gravity, the known techniques resulted in a theory that, when extrapolated to high energies, was plagued by an infinite number of infinities. This quantization of gravity was thought incurably sick, an approximation useful only when gravity is weak.

Since then, physicists have made several other attempts at quantizing gravity in the hope of finding a theory that would also work when gravity is strong. String theory, loop quantum gravity, causal dynamical triangulation and a few others have been aimed toward that goal. So far, none of these theories has experimental evidence speaking for it. Each has mathematical pros and cons, and no convergence seems in sight. But while these approaches were competing for attention, an old rival has caught up.

The theory called asymptotically (as-em-TOT-ick-lee) safe gravity was proposed in 1978 by Steven Weinberg. Weinberg, who would only a year later share the Nobel Prize with Sheldon Lee Glashow and Abdus Salam for unifying the electromagnetic and weak nuclear force, realized that the troubles with the naive quantization of gravity are not a death knell for the theory. Even though it looks like the theory breaks down when extrapolated to high energies, this breakdown might never come to pass. But to be able to tell just what happens, researchers had to wait for new mathematical methods that have only recently become available.

In quantum theories, all interactions depend on the energy at which they take place, which means the theory changes as some interactions become more relevant, others less so. This change can be quantified by calculating how the numbers that enter the theory — collectively called “parameters” — depend on energy. The strong nuclear force, for example, becomes weak at high energies as a parameter known as the coupling constant approaches zero. This property is known as “asymptotic freedom,” and it was worth another Nobel Prize, in 2004, to Frank Wilczek, David Gross and David Politzer.

A theory that is asymptotically free is well behaved at high energies; it makes no trouble. The quantization of gravity is not of this type, but, as Weinberg observed, a weaker criterion would do: For quantum gravity to work, researchers must be able to describe the theory at high energies using only a finite number of parameters. This is opposed to the situation they face in the naive extrapolation, which requires an infinite number of unspecifiable parameters. Furthermore, none of the parameters should themselves become infinite. These two requirements — that the number of parameters be finite and the parameters themselves be finite — make a theory “asymptotically safe.”

In other words, gravity would be asymptotically safe if the theory at high energies remains equally well behaved as the theory at low energies. In and of itself, this is not much of an insight. The insight comes from realizing that this good behavior does not necessarily contradict what we already know about the theory at low energies (from the early works of DeWitt and Feynman).

While the idea that gravity may be asymptotically safe has been around for four decades, it was only in the late 1990s, through research by Christof Wetterich, a physicist at the University of Heidelberg, and Martin Reuter, a physicist at the University of Mainz, that asymptotically safe gravity caught on. The works of Wetterich and Reuter provided the mathematical formalism necessary to calculate what happens with the quantum theory of gravity at higher energies. The strategy of the asymptotic safety program, then, is to start with the theory at low energies and use the new mathematical methods to explore how to reach asymptotic safety.

So, is gravity asymptotically safe? No one has proven it, but researchers use several independent arguments to support the idea. First, studies of gravitational theories in lower-dimensional space-times, which are much simpler to do, find that in these cases, gravity is asymptotically safe. Second, approximate calculations support the possibility. Third, researchers have applied the general method to studies of simpler, nongravitational theories and found it to be reliable.

The major problem with the approach is that calculations in the full (infinite dimensional!) theory space are not possible. To make the calculations feasible, researchers study a small part of the space, but the results obtained then yield only a limited level of knowledge. Therefore, even though the existing calculations are consistent with asymptotic safety, the situation has remained inconclusive. And there is another question that has remained open. Even if the theory is asymptotically safe, it might become physically meaningless at high energies because it might break some essential elements of quantum theory.

Even still, physicists can already put the ideas behind asymptotic safety to the test. If gravity is asymptotically safe — that is, if the theory is well behaved at high energies — then that restricts the number of fundamental particles that can exist. This constraint puts asymptotically safe gravity at odds with some of the pursued approaches to grand unification. For example, the simplest version of supersymmetry — a long-popular theory that predicts a sister particle for each known particle — is not asymptotically safe. The simplest version of supersymmetry has meanwhile been ruled out by experiments at the LHC, as have a few other proposed extensions of the Standard Model. But had physicists studied the asymptotic behavior in advance, they could have concluded that these ideas were not promising.

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Another study recently showed that asymptotic safety also constrains the masses of particles. It implies that the difference in mass between the top and bottom quark must not be larger than a certain value. If we had not already measured the mass of the top quark, this could have been used as a prediction.

These calculations rely on approximations that might turn out to be not entirely justified, but the results demonstrate the power of the method. The most important implication is that the physics at energies where the forces may be unified — usually thought to be hopelessly out of reach — is intricately related to the physics at low energies; the requirement of asymptotic safety connects them.

Whenever I speak to colleagues who do not themselves work on asymptotically safe gravity, they refer to the approach as “disappointing.” This comment, I believe, is born out of the thought that asymptotic safety means there isn’t anything new to learn from quantum gravity, that it’s the same story all the way down, just more quantum field theory, business as usual.

But not only does asymptotic safety provide a link between testable low energies and inaccessible high energies — as the above examples demonstrate — the approach is also not necessarily in conflict with other ways of quantizing gravity. That’s because the extrapolation central to asymptotic safety does not rule out that a more fundamental description of space-time — for example, with strings or networks — emerges at high energies. Far from being disappointing, asymptotic safety might allow us to finally connect the known universe to the quantum behavior of space-time.

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Lost In The Himalayas – A Fight for Survival Amongst the Himalayas for 43 Days

Sagar Rawal 2017 jan 08

Unusually this is not the story about a mountaineer surviving some great ordeal on one of the high peaks of the Himalayas. Instead this is the incredible story of a twenty-two year old man named James Scott who in December 1992 before starting his medical training at a hospital in Katmandu in Nepal, went for a walk, became lost in bad weather and 43 days later was rescued after having survived a month and half on two chocolate bars, one caterpillar and a copy of Great Expectations….oh and all during a Himalayan winter.

James’s story has appeared in many newspaper articles around the time of his rescue and James has told his tale for various newspapers and in a book about the ordeal entitled “Lost in the Himalayas: James Scott’s 43-Day Ordeal“. The story he tells begins with an initial trek on which they had hired and attempted to carry too much gear in their opinion. There is an old mountaineers’ saying that the more gear you weigh yourself down with, the more likely you are to need to use it. James therefore decided on the next trek to not bother with the down jackets and stiff walking boots but to take half a dozen t-shirts, a light ski jacket and to walk in trainers.

James’ lists his gear as such:

Odine to purify water and a sensible medical kit. I had about 10 pairs of underwear and socks, half a dozen T-shirts, a pair of red woollen long johns, a pair of karate pants, cotton long pants, and tracksuit pants. I had one sweatshirt, and a light ski jacket. I had a towel, my camera and four books: The Silence of the Lambs, Great Expectations, the Lonely Planet Guide to Nepal and a Guide to Trekking in Nepal. We had a map, but like most you buy in Nepal, it was old and confusing. My pack weighed about 10 kilos. James Scott: How I Survived

On this second trek he set out with Tim, the same friend who had accompanied him on the first trek, along the Helambu trail, a low level trail that never rises above the 3,000m contour. However after the first day James was persuaded by some other trekkers coming in the opposite direction, to change to the more visually rewarding Gosainkunda trail that winds its way up through spectacular mountainous territory to the holy lake of Gosainkunda before crossing the Gosainkunda pass at 4,610m.

Tim had to turn back at this point because of bad knees, but James continued with an Australian trekker that they had encountered. It was at this point that James made two decisions he came to regret, which was that he gave Tim the new map in order to find his way home, whilst keeping the older and much more confusing map for himself and that Tim took their only lighter with him as well. as James concedes in his own article:

I gave the new map to Tim without thinking. Only later did I appreciate how good that map was. We only had one lighter between us, and that was in Tim’s bag. They were mistakes. James Scott: How I Survived

James had been told at the start of the trek that if should begin to snow it was advisable to turn around and head back down. Therefore when the weather worsened near the top of the Gosainkunda trail James and his new trekking partner Mark had and an “amicable discussion” but decided to separate, with Mark carrying on and James retreating back down the way they had come.

In the worsening conditions James lost their footprints and the trail in the deepening snow and became disorientated. After having tried to follow a creek down stream for two days – a good survival technique for when you are lost as habitation tends to be in the valleys – James discovered that he could not continue because of the increasing steepness of the terrain, which was riddled with deep sheer-sided gullies filled with fast running streams, steep wooden slopes 3,000 feet high and torrential waterfalls.

James had walked himself into a corner being unable to continue downwards or to retreat back the way he had come. James was reduced to seeking shelter under a large rock overhang which was dry and protected from the wind by a stand of trees. Just to prove how well James was still thinking at this point however, he also was aware that there was a sizeable open area only a short distance from the shelter in which he believed he might be seen by a helicopter i.e. he was thinking of how he might be rescued, one vital part of survival preparation.

For the next seven weeks, James survived on a combination of his medical training to stave off dehydration and hypothermia i.e. he observed the colour of his urine and pinched his skin to test its elasticity. He tried eating the local flora, such as pine leaves and bamboo but found them unpalatable – he was not to know that pine needles contain a considerable amount of vitamin C which would stave off symptoms of malnutrition such as scurvy.

James mentions that he spent the first 10 days hideously hungry and that he had to devise various mental distractions to counter the constant thoughts of food. The human body can withstand a sizeable length of time without food, however the body will crave carbohydrate in any form, as that is the body’s preferred energy supply. James craved, fresh fruit and junk food, all good sources of carbohydrate and therefore as James’s body ran out of carbohydrate in the form of glycogen, so therefore his body would have begun to use the glycogen stored in his muscle tissue, thereby weakening him further.

The body does have a neat trick however to prevent the protein in the muscle tissue from being totally consumed. This protective process is the human body capacity to switch from burning carbohydrates in the form of glycogen in the blood (glycolysis) to a state when it utilises ketone bodies in the blood instead (ketosis). This is something that occurs naturally in humans whilst we sleep – a time when the blood glucose levels drop off naturally. However is can also happen during starvation and even permanently perhaps in some cultures that do not have access to enough foods containing carbohydrate.

James spent the next 43 days not moving around much and anyway as the time progressed, so he was unable to move far from the camp anyway due the loss of muscle. On day 40 James mentions that he tried to walk out of the camp because of his parlous state, but only managed 100 metres in two hours before falling down retching a vomiting, a dangerous condition that would have weakened his already dehydrated and malnourished state.

Towards the end of his ordeal, James contemplated suicide and decided that simply to stop drinking water would be the most ‘convenient’ method of dispatch, rather than slitting his wrists of trying to hang himself using his shoelaces. He estimated that death through dehydration would take about 3 days but during the night he woke up and regretted his decision to give up:

When I awoke it was pitch black; the moon had turned again. I knew I had given up and I shouldn’t have. I got up and tried to collect more ice but it was too cold too eat. My mouth stuck to it. I thought it was too late. James Scott: How I Survived

This proved fortunate as on the next day he woke to the sound of a helicopter and even in his week condition he managed to signal to it using his sleeping bag, but when it flew off he was unsure whether or not it had seen him. By this stage he was reaching the end of his very long tether and he recalls crawling back to his rock shelter and urinating which by now had turned black in colour.

He had been seen however and by the evening of that day he heard the sound of the first human voices other than his in 43 days.

When I first heard faint voices I thought I was hallucinating. But the voices persisted and I raised my head and whistled through my teeth. A whistle came back. I shouted, “Namaste | Hello |” and an echoing shout returned.

Slowly the shouts came nearer, but I was too weak to get up. I shouted “I am under this rock” then suddenly there were two dark figures on the ledge. They ran over and ripped the hood off my head. They were two Nepalese.

They asked, “Are you James Scott from Australia?” I said I was and, for the first time since I had been lost, I cried and cried. They were from Talu and they started hugging me and kissing me. I noticed one of them was barefoot; I knew that many villagers simply could not afford shoes. They were very brave. One of them said, “James Scott, you are a god. I asked why I was a god, and he said because no-one lived up here for more than 10 days. I said no, God must have kept me alive. James Scott: How I Survived

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