Some discoveries not well
understood by the majority of Humankind
understood by the majority of Humankind
QUANTUM MECHANICS
One of the greatest scientific achievements of physics in the 20th century is the discovery of quantum mechanics. It governs the dynamics of microscopic objects such as atoms and electrons. In this tiny world, things behave differently from the macroscopic world where classical mechanics rules. One feature of quantum mechanics is uncertainty. For example, the exact position of an electron in an atom is not knowable -- instead, the electron's position is probabilistically determined. The best metaphor for this is a cloud -- an electron in an atom is like a cloud with denser regions of the cloud representing places where the electron is most likely to be and less dense regions representing places where the electron is least likely to be. Another feature of quantum mechanics is discreteness. For example, an electron in an atom can only assume particular types of of motions, which are called states, and particular values for its energy, which are called energy levels.
Quantum mechanics has important philosophical implications due to the uncertainty that it implies. Because the future is not determined, free will is possible. (At the end of the 19th century before the development of quantum mechanics, philosophers had thought that people's actions were predetermined since the dynamics of everything was predictable using Newton's classical laws.)
The microscopic quantum world is so different from the macroscopic classical world that it is difficult for most people to comprehend. To quote from The Bible According to Einstein: "To venture into the atomic and the subatomic shall be like entering the stately pleasure-dome of Xanadu -- the scene shall be unimaginable." This book, which is written in biblical verse, presents an excellent intuitive description of quantum mechanics in terms of paths. Click here to go to that section of the book.
Chapter II: Paths
Ask among all paths, which is the good way?
And walk therein, for ye shall find there peace.
Now quantum mechanics has two formulations. And the first is the path integral. Now the position of a moving particle as time evolves shall constitute the particle's trajectory. Thus a trajectory shall be a curve through space and time. And because it is a curve in space and time, it shall also be a path. And a point on the path at a particular time shall be the position of the particle.
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The New Testament 213
And it is as though thou walkest along a wooded valley trail between two mountains. And thou beginst thy walk at the beginning of the trail. And thirty minutes later, thou hast traversed one mile of track. And one hour later, thou art two miles from the start. And two hours later, thou finishest thy walk. And since thou traverst the trail in a steady manner, anyone knows where thou art at any time. Thy motion is predictable. And thy positions at various times constitute a known trajectory. Thus in this example, the trajectory is the trail itself.
Now in classical mechanics, there shall be but one trajectory, or path. And this path shall be computable from Newton's laws. And it shall be called the classical trajectory. And knowledge of this path shall provide knowledge of the position of any object in the future, at the present, or in the past.
In classical mechanics, it is as though thou be infinitely lazy. And choosest thou the path of least resistance. And avoidest thou steep mountain slopes, so that thou walkest along the center of the valley. And though thou be tempted to take a short cut, it involves climbing and descending. And thou mightest want to pass along a longer, perhaps-more-scenic route, but lazy as thou art, takest thou the easy path, the lazy path.
Only poets choose the path less travelled by.
And for thee, the classical trajectory shall be the predictable, well-travelled trail. But in quantum mechanics, thou shalt be free. Thou shalt be allowed to walk along all paths.
Quantum mechanics -- it be the democratization of dictatorial classical-mechanics laws.
So in a quantum mechanical world, an object shall transverse all paths. But some paths shall be more preferable than others. And the most preferred path of all shall be the classical trajectory. And because all paths are included, it shall be impossible to predict with certainty where an object be at a given moment. Thus uncertainty shall be a property of quantum mechanics. And this effect shall have a name -- the uncertainty principle shall be its name.
And suppose thou livest in a quantum world and thou beginst thy walk. Now in this quantum case, thou dost not plan thy walk. And thou art only somewhat lazy. So most of the time, movest thou along the local trail of least resistance. But sometimes, decidest thou to profit from a short cut. And sometimes, thou decidest to ascend a little hill. And sometimes, thou decidest to take a longer route. And these decisions are made randomly but preferably, because preferest thou the easy trails.
Wormholes
In physics and fiction, a wormhole is a hypothetical topological feature of spacetime that would be, fundamentally, a "shortcut" through spacetime. For a simple visual explanation of a wormhole, consider spacetime visualized as a two-dimensional (2D) surface (see illustration, right). If this surface is folded along a third dimension, it allows one to picture a wormhole "bridge". (Please note, though, that this image is merely a visualization displayed to convey an essentially unvisualisable structure existing in 4 or more dimensions. The parts of the wormhole could be higher-dimensional analogues for the parts of the curved 2D surface; for example, instead of mouths which are circular holes in a 2D plane, a real wormhole's mouths could be spheres in 3D space.) A wormhole is, in theory, much like a tunnel with two ends each in separate points in spacetime.
There is no observational evidence for wormholes, but on a theoretical level there are valid solutions to the equations of the theory of general relativity which contain wormholes. The first type of wormhole solution discovered was the Schwarzschild wormhole which would be present in the Schwarzschild metric describing an eternal black hole, but it was found that this type of wormhole would collapse too quickly for anything to cross from one end to the other. Wormholes which could actually be crossed, known as traversable wormholes, would only be possible if exotic matter with negative energy density could be used to stabilize them (many physicists such as Stephen Hawking,[1] Kip Thorne,[2] and others[3][4][5] believe that the Casimir effect is evidence that negative energy densities are possible in nature). Physicists have also not found any natural process which would be predicted to form a wormhole naturally in the context of general relativity, although the quantum foam hypothesis is sometimes used to suggest that tiny wormholes might appear and disappear spontaneously at the Planck scale.[6][7] It has also been proposed that if a tiny wormhole held open by a negative-mass cosmic string had appeared around the time of the Big Bang, it could have been inflated to macroscopic size by cosmic inflation.[8]
The American theoretical physicist John Archibald Wheeler coined the term wormhole in 1957; however, in 1921, the German mathematician Hermann Weyl already had proposed the wormhole theory, in connection with mass analysis of electromagnetic field energy.[9]
This analysis forces one to consider situations...where there is a net flux of lines of force, through what topologists would call "a handle" of the multiply-connected space, and what physicists might perhaps be excused for more vividly terming a "wormhole".
—John Wheeler in Annals of Physics
MULTIVERSE
The multiverse (or meta-universe, metaverse) is the hypothetical set of multiple possible universes (including the historical universe we consistently experience) that together comprise everything that exists: the entirety of space, time, matter, and energy as well as the physical laws and constants that describe them. The term was coined in 1895 by the American philosopher and psychologist William James.[1] The various universes within the multiverse are sometimes called parallel universes.
The structure of the multiverse, the nature of each universe within it and the relationship between the various constituent universes, depend on the specific multiverse hypothesis considered. Multiverses have been hypothesized in cosmology, physics, astronomy, philosophy, transpersonal psychology and fiction, particularly in science fiction and fantasy. In these contexts, parallel universes are also called "alternative universes", "quantum universes", "interpenetrating dimensions", "parallel dimensions", "parallel worlds", "alternative realities", and "alternative timelines", among others.
The multiverse (or meta-universe, metaverse) is the hypothetical set of multiple possible universes (including the historical universe we consistently experience) that together comprise everything that exists: the entirety of space, time, matter, and energy as well as the physical laws and constants that describe them. The term was coined in 1895 by the American philosopher and psychologist William James.[1] The various universes within the multiverse are sometimes called parallel universes.
The structure of the multiverse, the nature of each universe within it and the relationship between the various constituent universes, depend on the specific multiverse hypothesis considered. Multiverses have been hypothesized in cosmology, physics, astronomy, philosophy, transpersonal psychology and fiction, particularly in science fiction and fantasy. In these contexts, parallel universes are also called "alternative universes", "quantum universes", "interpenetrating dimensions", "parallel dimensions", "parallel worlds", "alternative realities", and "alternative timelines", among others.
Dimensions and parallel universes
Freaky Physics Proves Parallel Universes Exist
By John Brandon
Published April 05, 2010 | FOXNews.com
Look past the details of a wonky discovery by a group of California scientists -- that a quantum state is now observable with the human eye -- and consider its implications: Time travel may be feasible. Doc Brown would be proud.Freaky Physics Proves Parallel Universes Exist
By John Brandon
Published April 05, 2010 | FOXNews.com
The strange discovery by quantum physicists at the University of California Santa Barbara means that an object you can see in front of you may exist simultaneously in a parallel universe -- a multi-state condition that has scientists theorizing that traveling through time may be much more than just the plaything of science fiction writers.
And it's all because of a tiny bit of metal -- a "paddle" about the width of a human hair, an item that is incredibly small but still something you can see with the naked eye.
UC Santa Barbara's Andrew Cleland cooled that paddle in a refrigerator, dimmed the lights and, under a special bell jar, sucked out all the air to eliminate vibrations. He then plucked it like a tuning fork and noted that it moved and stood still at the same time.
That sounds contradictory, and it's nearly impossible to understand if your last name isn't Einstein. But it actually happened. It's a freaky fact that's at the heart of quantum mechanics.
How Is That Possible?
To even try to understand it, you have to think really, really small. Smaller than an atom. Electrons, which circle the nucleus of an atom, are swirling around in multiple states at the same time -- they're hard to pin down. It's only when we measure the position of an electron that we force it to have a specific location. Cleland's breakthrough lies in taking that hard-to-grasp yet true fact about the atomic particle and applying it to something visible with the naked eye.
What does it all mean? Let's say you're in Oklahoma visiting your aunt. But in another universe, where your atomic particles just can't keep up, you're actually at home watching "The Simpsons." That may sound far-fetched, but it's based on real science.
"When you observe something in one state, one theory is it split the universe into two parts," Cleland told FoxNews.com, trying to explain how there can be multiple universes and we can see only one of them.
The multi-verse theory says the entire universe "freezes" during observation, and we see only one reality. You see a soccer ball flying through the air, but maybe in a second universe the ball has dropped already. Or you were looking the other way. Or they don't even play soccer over there.
Sean Carroll, a physicist at the California Institute of Technology and a popular author, accepts the scientific basis for the multi-verse -- even if it cannot be proven.
"Unless you can imagine some super-advanced alien civilization that has figured this out, we aren't affected by the possible existence of other universes," Carroll said. But he does think "someone could devise a machine that lets one universe communicate with another."
It all comes down to how we understand time.
Carroll suggests that we don't exactly feel time -- we perceive its passing. For example, time moves fast on a rollercoaster and very slowly during a dull college lecture. It races when you're late for work . . . but the last few minutes before quitting time seem like hours.
Back to the Future
"Time seems to be a one-way street that runs from the past to the present," says Fred Alan Wolf, a.k.a. Dr. Quantum, a physicist and author. "But take into consideration theories that look at the level of quantum fields ... particles that travel both forward and backward in time. If we leave out the forward-and-backwards-in-time part, we miss out on some of the physics."
Wolf says that time -- at least in quantum mechanics -- doesn't move straight like an arrow. It zig-zags, and he thinks it may be possible to build a machine that lets you bend time.
Consider Sergei Krikalev, the Russian astronaut who flew six space missions. Richard Gott, a physicist at Princeton University, says Krikalev aged 1/48th of a second less than the rest of us because he orbited at very high speeds. And to age less than someone means you've jumped into the future -- you did not experience the same present. In a sense, he says, Krikalev time-traveled to the future -- and back again!
"Newton said all time is universal and all clocks tick the same way," Gott says. "Now with Einstein's theory of Special Relativity we know that travel into the future is possible. With Einstein's theory of gravity, the laws of physics as we understand them today suggest that even time travel to the past is possible in principle. But to see whether time travel to the past can actually be realized we may have to learn new laws of physics that step in at the quantum level."
And for that, you start with a very tiny paddle in a bell jar.
Cleland has proved that quantum mechanics scale to slightly larger sizes. The next challenge is to learn how to control quantum mechanics and use it for even larger objects. Do so -- and we might be able to warp to parallel universes just by manipulating a few electrons.
"Our concepts of cause and effect will fly out the window," says Ben Bova, the science fiction author. "People will -- for various reasons -- try to fix the past or escape into the future. But we may never notice these effects, if the universe actually diverges. Maybe somebody already has invented a time machine and our history is being constantly altered, but we don’t notice the kinks in our path through time."
The theory of everything
The theory of everything (TOE) is a putative theory of theoretical physics that fully explains and links together all known physical phenomena, and, ideally, has predictive power for the outcome of any experiment that could be carried out in principle.
Initially, the term was used with an ironic connotation to refer to various overgeneralized theories. For example, a great-grandfather of Ijon Tichy—a character from a cycle of Stanisław Lem's science fiction stories of the 1960s—was known to work on the "General Theory of Everything". Physicist John Ellis[1] claims to have introduced the term into the technical literature in an article in Nature in 1986.[2] Over time, the term stuck in popularizations of quantum physics to describe a theory that would unify or explain through a single model the theories of all fundamental interactions of nature.
There have been many theories of everything proposed by theoretical physicists over the last century, but none have been confirmed experimentally. The primary problem in producing a TOE is that the accepted theories of quantum mechanics and general relativity are hard to combine. Their mutual incompatibility argues that they are incomplete, or at least not fully understood taken individually. (For more, see unsolved problems in physics).
Based on theoretical holographic principle arguments from the 1990s, many physicists believe that 11-dimensional M-theory, which is described in many sectors by matrix string theory, in many other sectors by perturbative string theory is the complete theory of everything, although there is no widespread consensus and M-theory is not a completed theory but rather an approach for producing one.
A Theory of Everything?
Some physicists believe string theory
may unify the forces of nature
by Brian Greene
The fundamental particles of the universe that physicists have identified—electrons, neutrinos, quarks, and so on—are the "letters" of all matter. Just like their linguistic counterparts, they appear to have no further internal substructure. String theory proclaims otherwise. According to string theory, if we could examine these particles with even greater precision—a precision many orders of magnitude beyond our present technological capacity—we would find that each is not pointlike but instead consists of a tiny, one-dimensional loop. Like an infinitely thin rubber band, each particle contains a vibrating, oscillating, dancing filament that physicists have named a string.
In the figure at right, we illustrate this essential idea of string theory by starting with an ordinary piece of matter, an apple, and repeatedly magnifying its structure to reveal its ingredients on ever smaller scales. String theory adds the new microscopic layer of a vibrating loop to the previously known progression from atoms through protons, neutrons, electrons, and quarks.
Although it is by no means obvious, this simple replacement of point-particle material constituents with strings resolves the incompatibility between quantum mechanics and general relativity (which, as currently formulated, cannot both be right). String theory thereby unravels the central Gordian knot of contemporary theoretical physics. This is a tremendous achievement, but it is only part of the reason string theory has generated such excitement.
In Einstein's day, the strong and weak forces had not yet been discovered, but he found the existence of even two distinct forces—gravity and electromagnetism—deeply troubling. Einstein did not accept that nature is founded on such an extravagant design. This launched his 30-year voyage in search of the so-called unified field theory that he hoped would show that these two forces are really manifestations of one grand underlying principle. This quixotic quest isolated Einstein from the mainstream of physics, which, understandably, was far more excited about delving into the newly emerging framework of quantum mechanics. He wrote to a friend in the early 1940s, "I have become a lonely old chap who is mainly known because he doesn't wear socks and who is exhibited as a curiosity on special occasions."
Einstein was simply ahead of his time. More than half a century later, his dream of a unified theory has become the Holy Grail of modern physics. And a sizeable part of the physics and mathematics community is becoming increasingly convinced that string theory may provide the answer. From one principle—that everything at its most microscopic level consists of combinations of vibrating strands—string theory provides a single explanatory framework capable of encompassing all forces and all matter.
String theory proclaims, for instance, that the observed particle properties—that is, the different masses and other properties of both the fundamental particles and the force particles associated with the four forces of nature (the strong and weak nuclear forces, electromagnetism, and gravity)—are a reflection of the various ways in which a string can vibrate. Just as the strings on a violin or on a piano have resonant frequencies at which they prefer to vibrate—patterns that our ears sense as various musical notes and their higher harmonics—the same holds true for the loops of string theory. But rather than producing musical notes, each of the preferred mass and force charges are determined by the string's oscillatory pattern. The electron is a string vibrating one way, the up-quark is a string vibrating another way, and so on.
Far from being a collection of chaotic experimental facts, particle properties in string theory are the manifestation of one and the same physical feature: the resonant patterns of vibration—the music, so to speak—of fundamental loops of string. The same idea applies to the forces of nature as well. Force particles are also associated with particular patterns of string vibration and hence everything, all matter and all forces, is unified under the same rubric of microscopic string oscillations—the "notes" that strings can play.
A theory to end theories
For the first time in the history of physics we therefore have a framework with the capacity to explain every fundamental feature upon which the universe is constructed. For this reason string theory is sometimes described as possibly being the "theory of everything" (T.O.E.) or the "ultimate" or "final" theory. These grandiose descriptive terms are meant to signify the deepest possible theory of physics—a theory that underlies all others, one that does not require or even allow for a deeper explanatory base.
In practice, many string theorists take a more down-to-earth approach and think of a T.O.E. in the more limited sense of a theory that can explain the properties of the fundamental particles and the properties of the forces by which they interact and influence one another. A staunch reductionist would claim that this is no limitation at all, and that in principle absolutely everything, from the big bang to daydreams, can be described in terms of underlying microscopic physical processes involving the fundamental constituents of matter. If you understand everything about the ingredients, the reductionist argues, you understand everything.
The reductionist philosophy easily ignites heated debate. Many find it fatuous and downright repugnant to claim that the wonders of life and the universe are mere reflections of microscopic particles engaged in a pointless dance fully choreographed by the laws of physics. Is it really the case that feelings of joy, sorrow, or boredom are nothing but chemical reactions in the brain—reactions between molecules and atoms that, even more microscopically, are reactions between some of the fundamental particles, which are really just vibrating strings?
In response to this line of criticism, Nobel laureate Steven Weinberg cautions in Dreams of a Final Theory:
At the other end of the spectrum are the opponents of reductionism who are appalled by what they feel to be the bleakness of modern science. To whatever extent they and their world can be reduced to a matter of particles or fields and their interactions, they feel diminished by that knowledge....I would not try to answer these critics with a pep talk about the beauties of modern science. The reductionist worldview is chilling and impersonal. It has to be accepted as it is, not because we like it, but because that is the way the world works.
Some agree with this stark view, some don't.
Others have tried to argue that developments such as chaos theory tell us that new kinds of laws come into play when the level of complexity of a system increases. Understanding the behavior of an electron or quark is one thing; using this knowledge to understand the behavior of a tornado is quite another. On this point, most agree. But opinions diverge on whether the diverse and often unexpected phenomena that can occur in systems more complex than individual particles truly represent new physical principles at work, or whether the principles involved are derivative, relying, albeit in a terribly complicated way, on the physical principles governing the enormously large number of elementary constituents.
My own feeling is that they do not represent new and independent laws of physics. Although it would be hard to explain the properties of a tornado in terms of the physics of electrons and quarks, I see this as a matter of calculational impasse, not an indicator of the need for new physical laws. But again, there are some who disagree with this view.
A fresh start for science
What is largely beyond question, and is of primary importance to the journey described in my book The Elegant Universe, is that even if one accepts the debatable reasoning of the staunch reductionist, principle is one thing and practice quite another. Almost everyone agrees that finding the T.O.E. would in no way mean that psychology, biology, geology, chemistry, or even physics had been solved or in some sense subsumed. The universe is such a wonderfully rich and complex place that the discovery of the final theory, in the sense we are describing here, would not spell the end of science.
Quite the contrary: The discovery of the T.O.E.—the ultimate explanation of the universe at its most microscopic level, a theory that does not rely on any deeper explanation—would provide the firmest foundation on which to build our understanding of the world. Its discovery would mark a beginning, not an end. The ultimate theory would provide an unshakable pillar of coherence forever assuring us that the universe is a comprehensible place.
