Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Yale scientist says clues to string theory may be visible in Big Bang aftermath

13.05.2004


Scientists studying the Big Bang say that it is possible that string theory may one day be tested experimentally via measurements of the Big Bang’s afterglow.

Richard Easther, assistant professor of physics at Yale University will discuss the possibility at a meeting at Stanford University Wednesday, May 12, titled “Beyond Einstein: From the Big Bang to Black Holes.” Easther’s colleagues are Brian Greene of Columbia University, William Kinney of the University at Buffalo, SUNY, Hiranya Peiris of Princeton University and Gary Shiu of the University of Wisconsin.

String theory attempts to unify the physics of the large (gravity) and the small (the atom). These are now described by two theories, general relativity and quantum theory, both of which are likely to be incomplete.



Critics have disdained string theory as a “philosophy” that cannot be tested. However, the results of Easther and his colleagues suggest that observational evidence supporting string theory may be found in careful measurements of the Cosmic Microwave Background (CMB), the first light to emerge after the Big Bang.

“In the Big Bang, the most powerful event in the history of the Universe, we see the energies needed to reveal the subtle signs of string theory,” said Easther.

String theory reveals itself only over extreme small distances and at high energies. The Planck scale measures 10-35 meters, the theoretical shortest distance that can be defined. In comparison, a tiny hydrogen atom, 10-10 meters across, is ten trillion trillion times as wide. Similarly, the largest particle accelerators generate energies of 1015 electron volts by colliding sub-atomic particles. This energy level can reveal the physics of quantum theory, but is still roughly a trillion times lower than the energy required to test string theory.

Scientists say that the fundamental forces of the Universe – gravity (defined by general relativity), electromagnetism, “weak” radioactive forces and “strong” nuclear forces (all defined by quantum theory) – were united in the high-energy flash of the Big Bang, when all matter and energy was confined within a sub-atomic scale. Although the Big Bang occurred nearly 14 billion years ago, its afterglow, the CMB, still blankets the entire universe and contains a fossilized record of the first moments of time.

The Wilkinson Microwave Anisotropy Probe (WMAP) studies the CMB and detects subtle temperature differences, within this largely uniform radiation, glowing at only 2.73 degrees Celsius above absolute zero. The uniformity is evidence of “inflation,” a period when the expansion of the Universe accelerated rapidly, around 10-33 seconds after the Big Bang. During inflation, the Universe grew from an atomic scale to a cosmic scale, increasing its size a hundred trillion trillion times over. The energy field that drove inflation, like all quantum fields, contained fluctuations. These fluctuations, locked into the cosmic microwave background like waves on a frozen pond, may contain evidence for string theory.

Easther and his colleagues compare the rapid cosmic expansion that occurred just after the Big Bang to enlarging a photograph to reveal individual pixels. While physics at the Planck scale made a “ripple” 10-35 meters across, thanks to the expansion of the Universe the fluctuation might now span many light years.

Easther stressed it is a long shot that string theory might leave measurable effects on the microwave background by subtly changing the pattern of hot and cold spots. However, string theory is so hard to test experimentally that any chance is worth trying. Successors to WMAP, such as CMBPol and the European mission, Planck, will measure the CMB with unprecedented accuracy.

The modifications to the CMB arising from string theory could deviate from the standard prediction for the temperature differences in the cosmic microwave background by as much as 1%. However, finding a small deviation from a dominant theory is not without precedent. As an example, the measured orbit of Mercury differed from what was predicted by Isaac Newton’s law of gravity by around seventy miles per year. General relativity, Albert Einstein’s law of gravity, could account for the discrepancy caused by a subtle warp in spacetime from the Sun’s gravity speeding Mercury’s orbit.

Janet Rettig Emanuel | EurekAlert!
Further information:
http://www-conf.slac.stanford.edu/einstein/
http://www.yale.edu/

More articles from Physics and Astronomy:

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

nachricht Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>