Archive for the ‘Holographic Universe’ Category

Holographic Universe: Discovery

Science News

Holographic Universe: Discovery Could Herald New Era In Fundamental Physics

ScienceDaily (Feb. 4, 2009) — Cardiff University researchers, who are part of a British-German team searching the depths of space to study gravitational waves, may have stumbled on one of the most important discoveries in physics, according to an American physicist.


Craig Hogan, a physicist at Fermilab Centre for Particle Astrophysics in Illinois is convinced that he has found proof in the data of the gravitational wave detector GEO600 of a holographic Universe – and that his ideas could explain mysterious noise in the detector data that has not been explained so far.

The British-German team behind the GEO600, which includes scientists from the School of Physics and Astronomy’s Gravitational Physics Group, will now carry out new experiments in the coming months to yield more evidence about Craig Hogan’s assumptions. If proved correct, it could help in the quest to bring together quantum mechanics and Einstein’s theory of gravity.

In order to test the theory of holographic noise, the frequency of GEO600´s maximum sensitivity will be shifted towards ever higher frequencies. The frequency of maximum sensitivity is the tone that the detector can hear best. It is normally adjusted to offer the best chance for hearing exploding stars or merging black holes.

Even if it turns out that the mysterious noise is the same at high frequencies as at the lower ones, this will not constitute proof for Hogan’s hypothesis. It would, however, provide a strong motivation for further study. The sensitivity of GEO600 will then be significantly improved by using ‘squeezed vacuum’ and by the installation of a mode filter in a new vacuum chamber. The technology of ‘squeezed vacuum’ was particularly refined in Hannover and would be used in a gravitational wave detector for the first time.

Professor Jim Hough of Glasgow University, one of the pioneer developers of gravitational wave detectors, says: ‘Craig Hogan made a very interesting prediction. It may be the first of a number of unexpected possibilities to be investigated as gravitational wave detectors become more sensitive.’

Professor Bernard Schutz, Professor at the School of Physics and Astronomy, member of the Gravitational Physics Group at the School, and recently elected as an Honorary Fellow of the Royal Astronomical Society said: “It would be truly remarkable if GEO600 is sensitive to the quantum nature of space and time. The only way to confirm that would be to carry out controlled experiments, the results of which can be solely attributed to holographic noise. Such an experiment would herald a new era in fundamental physics”.

Professor Dr. Karsten Danzmann, director of the Hannover Albert-Einstein-Institute, said: “We are very eager to find out what we can learn about the possible holographic noise over the course of the coming year. GEO600 is the only experiment in the world able to test this controversial theory at this time. Unlike the other large laser interferometers, GEO600 reacts particularly sensitively to lateral movement of the beam splitter because it is constructed using the principle of signal recycling. Normally this is inconvenient, but we need the signal recycling to compensate for the shorter arm lengths compared to other detectors. The holographic noise, however, produces exactly such a lateral signal and so the disadvantage becomes an advantage in this case. You could say that this has placed us in the very centre of a tornado in fundamental research!

Searching for the graininess of space

The smallest possible fraction of distance is called the ‘Planck length” by physicists. Its value is 1.6 x 10-35 m – this is impossible to measure by itself. The established physical theories cease to function at this scale. GEO600 scientists are testing a theory by US physicist Craig Hogan, who is convinced he can hear the noise of space quanta in the data of the gravitational wave detector GEO600. Hogan suggests that the mirrors in an interferometer wander relative to one another in very rapid steps of the tiny Planck amount, that accumulate during the time of a measurement into something as large as a gravitational wave would produce. Hogan and the GEO600 scientists are following up the question whether a certain ‘noise signal’ in the data recorded by the detector can be traced back to the graininess of space and time.

GEO600

Because of its innovative and reliable technology, GEO 600 has gained an excellent worldwide reputation and is considered a think-tank for international gravitational wave observation. It was here that the most modern lasers in the world were developed which are being used in all the gravitational wave observatories in the world today. Researchers at GEO600 are taking technology a step further with ‘squeezed vacuum’. This technology is designated for use in the third generation of gravitational wave detectors.

GEO600 is a joint project of scientists of the Max Planck Institute for Gravitational Physics (Albert Einstein Institute, or AEI), Leibniz Universität Hannover, Cardiff University, the University of Glasgow and the University of Birmingham. It is funded jointly by the Max Planck Society in Germany and the Science and Technology Facilities Council in UK.

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Where are they?

Why Are We Alone? The Fermi Paradox.

Fermi Paradox

Where Are They?

Nobel prize-winning Italian physicist Enrico Fermi asked the question “Where are they?” regarding the question of life existing elsewhere in the universe. If one assumes the mediocrity principle – that the development of life on earth is typical in comparison to the rest of the universe – we should see evidence of other life. The Fermi paradox is the contradiction between estimates of the number of extraterrestrial civilizations and a corresponding lack of evidence of these civilizations – both physical and radio (the Great Silence).

It’s obvious that civilizations can exist – we are one. Why not others?

Assumptions

  • The universe is extremely old. Its current age is estimated at approximately 13.73 billion years
  • The number of stars in the visible universe is extremely large – approximately 5 x 1022.
  • Some of these stars will have habitable planets which develop intelligent life that can produce radio signals.
  • Interstellar travel is possible, and some civilizations desire to colonize stars.

More intelligent estimates of the Drake Equation have been possible with recent advances in astronomy and astrobiology. One estimate in the July 2000 edition of Scientific American suggests the number of civilizations that have existed in our galaxy in the past is 12 billion, with 1,000 of them still transmitting radio evidence of their existence.

Despite those assumptions, limited radio searches of the skies for nearly 50 years have found no evidence of extraterrestrial life. And, it would take only one civilization that desires so between 5 and 50 million years to colonize the entire galaxy – a blink of an eye compared to the age of the universe. So where are they?

Possible Solutions

Clearly there must be something wrong with assumptions that have been made. Some possible resolutions to the Fermi Paradox are:

  • A Great Filter drastically limits the number of civilizations in the universe. Life faces existential risks which are difficult to overcome. For example, the development of the ability to communicate by radio occurs at roughly the same time as the development of nuclear weapons. Professor Nick Bostrom claims that the lack of evidence of extraterrestrial life is a positive sign for the outcome of our own existence.
  • One or more of our assumptions is wrong. Perhaps we’re not searching in the right way. Before the invention of radio, for example, the only way to search for life would have been optically. Perhaps neutrinos or some other communication method is used instead.
  • Transcendence – Life passing through a singularity stage may discover a way to exit the universe, or find more meaningful ways of existing. Maybe we are boring and they have no interest in making contact or communicating with us.
  • Perhaps we are living in a simulation.
  • The Zoo hypothesis – we are being isolated intentionally.
  • Perhaps abiogenesis occurs less frequently than current assumptions and we really are alone.
    from: Nested Universe

What do you think?