* Astronomy

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RE: Theory of Everything

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A sophisticated, new analysis has revealed that the next frontier in particle physics is farther away than once thought. New forms of matter not predicted by the Standard Model of particle physics are most likely twice as massive as theorists had previously calculated. The result comes from a just-published study that was featured on the cover of Physical Review Letters.
To see the infinitely small bits of matter that make up our universe, physicists build ever more powerful accelerators, the microscopes they use to see matter. But while the trend is to more powerful accelerators, the precision achieved by some less powerful ones can pinpoint the best places to look for never-before-seen particles. It turns out that high-precision measurements can reveal the signature of new forms of matter.
In a recent study, Jefferson Lab scientists combined data from two Jefferson Lab experiment groups, G-Zero and HAPPEx, and from the PVA4 collaboration at Mainz and SAMPLE at MIT-Bates. These groups conducted experiments in which electrons were used to precisely probe the nucleus of the atom.
The experiments studied the weak nuclear force, one of the four forces of nature. Using the experimental data from all of these groups, Jefferson Lab researchers precisely determined the effects of the weak force on the building blocks of the proton, up and down quarks.
Moreover, when this new analysis was combined with still other measurements, it raised the predicted mass scale for the discovery of new particles to about one Tera-electron-volts (1 TeV) more than a factor of two higher than previously thought. The discovery is noteworthy, because experimental improvements of this magnitude rarely occur more often than once in a decade.
The result also shows one possible impact of data from the upcoming Q-weak experiment in Jefferson Lab's Hall C. It shows that, with Q-weak's anticipated accuracy, the experiment will improve the current analysis's measurement of the effects of the weak force on up and down quarks by a factor of five. It could also raise the predicted mass for new particles another 1 TeV.

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Finding evidence to back up a theory of everything was always going to be difficult. Now two particle physicists say they may have tracked some down - lurking inside black holes.
The pair's calculations have revealed that black holes might be harbouring enigmatic hypothetical entities called magnetic monopoles. If they are, not only would physicists have stumbled upon a key ingredient for a theory of everything, but it may explain why some black holes rotate.
Physicist Paul Dirac first proposed magnetic monopoles in 1931. Unlike magnetic poles, which come in north and south pairs, monopoles carry just a single magnetic "charge". Dirac proposed that monopoles are necessary to explain why electrons carry just a single electric charge.
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Early String Theory research and the anomalies that led to the introduction of M-theory, the next possible "Theory Of Everything", an excerpt from NOVA's Elegant Universe

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Planck Mass

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Planck Length

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RE: Theory of Everything

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The Big Questions: Is the universe deterministic?

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Gravity

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GRAVITY IS NORMAL DOWN TO THE 100-nm LEVEL.

Gravity at the level of planets is well studied, and was known accurately even in Newton's day. This is owing to the fact that the other physical forces, such as the strong and weak nuclear forces, don't operate over such great distances, and electromagnetic forces between immense far-apart, electrically-neutral objects like planets are dilute.
Gravity at shorter lengths, by contrast, is harder to measure, partly because all the other forces are in full play.
Furthermore, theories of particle interactions hypothesizing the existence of additional spatial dimensions suggest that the strength of gravity will depart from Newton's famous inverse-square formulation.
To test these propositions, various tabletop setups have been devised to probe gravity below the micron level.
One previous experiment, conducted by Eric Adelberger's group at the University of Washington, ruled out extra gravity components having strength comparable to conventional gravity down to a size scale of about 100 microns .

A new experiment, carried out by a Indiana/Purdue/Lucent/Florida/Wabash collaboration examines a shorter distance scale-100 nm - but is able to rule out
only corrections to gravity that are, in fact, a trillion times larger than gravity itself. Nevertheless, such measurements help to constrain the general pursuit of unified theories of particle physics, including explanations of gravity.

The sort of "Yukawa" corrections being sought are analogous to the force proposed by Hideki Yukawa in the 1930s to explain how mesons transmit the nuclear force between nucleons and would come about because of transmission of the presumed force particles associated with the hypothetical extra dimensions. The present measurements improve the
exclusion of such corrections by a factor of ten. According to Ricardo Decca of Indiana University-Purdue University, the sensitivity of the apparatus should grow by a factor of a hundred over the next year. The size of the sample is smaller here than in many other tabletop gravity experiments.

The flea-sized torsional apparatus must operate with such concern for forces acting over small distances that one of the chief goals here is reducing the background produced by the Casimir force - a quantum effect in which two very close objects are drawn together because of the way they exclude vacuum fluctuations (that is, the
spontaneous creation of pairs of virtual particles) from occurring in a slender volume of space - between a flat plane and sphere lying only 200 nm apart.

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