Fifth force

In physics , the fifth force denotes a hypothetical fifth interaction in addition to gravitation , weak , electromagnetic and strong interaction.

It is often used to describe forces that, like gravity, are proportional to the mass (more precisely: coupled to the energy-momentum tensor ), but decrease faster with increasing distance than according to Newton's law of gravitation , i.e. H. faster than with . ${\displaystyle {\frac {1}{r^{2}}}}$

This hypothesis aroused a certain amount of interest from 1986, when a summarizing evaluation of old experiments of the Eötvös type suggested an effect ( Ephraim Fischbach and others). The first attempts to reproduce the experiment seem to be successful, but with more sensitive experiments it became clear in the next few years that the effect, if any, had to be extremely small.

The search for deviations from Newton's law of gravitation has so far covered four size scales:

experiment	Magnitude
Measurement of the planetary orbits	approx. 1 astronomical unit
Surveying satellite orbits	300 to 30,000 km
Gravity measurements on towers, in mines and the deep sea	some 100 to some 1000 m
Laboratory experiments with gravitational balances	1 to 10 m

An active research area is still the millimeter range and below. Deviations from the behavior would be to be expected here if some of the higher dimensions predicted by string theory are not limited to Planck length , the so-called theory of the large extra dimensions . ${\displaystyle {\frac {1}{r^{2}}}}$

literature

• Allan Franklin: The rise and fall of the fifth force - discovery, pursuit, and justification in modern physics. AIP, New York 1993, ISBN 1-56396-119-9 .
• Ephraim Fischbach, et al .: The search for non-Newtonian gravity. Springer, New York 1999, ISBN 0-387-98490-9 .
• Ephraim Fischbach, Carrick Talmadge: Six years of the fifth force . In: Nature . tape 356 , no. 6366 , March 19, 1992, pp. 207-215 , doi : 10.1038 / 356207a0 .
• Ephraim Fischbach, Carrick Talmadge: Ten Years of the Fifth Force . In: High Energy Physics - Phenomenology . June 5, 1996, arxiv : hep-ph / 9606249 .

Web links

• The EOET-Wash Group: Laboratory tests of Gravitational and sub-Gravitational Physics (Engl.)

Individual evidence

1. ↑ Clifford M. Will: The Confrontation between General Relativity and Experiment. In: Living Reviews in Relativity . Volume 9, 2006, p. 3, doi: 10.12942 / lrr-2006-3 .
2. ↑ Ephraim Fischbach, Daniel Sudarsky, Aaron Szafer, Carrick Talmadge, S. H. Aronson: Reanalysis of the Eötvös experiment. In: Physical Review Letters . tape 56 , no. 13 , March 31, 1986, pp. 1427-1427 , doi : 10.1103 / PhysRevLett.56.1427 .
3. ↑ C. D. Hoyle et al. a .: Submillimeter tests of the gravitational inverse-square law . In: Physical Review D . tape 70 , no. 4 , August 26, 2004, p. 042004 , doi : 10.1103 / PhysRevD.70.042004 , arxiv : hep-ph / 0405262 .
4. ↑ J. Chiaverini, S. J. Smullin, A. A. Geraci, D. M. Weld, A. Kapitulnik: New Experimental Constraints on Non-Newtonian Forces below 100 microns. In: Phys. Rev. Lett. 90, 2003, 151101, doi: 10.1103 / PhysRevLett.90.151101 , arxiv : hep-ph / 0209325 .
5. ↑ Nima Arkani-Hamed, Savas Dimopoulos, Gia Dvali: The Hierarchy Problem and New Dimensions at a Millimeter. In: Phys. Lett. B429, 1998, pp. 263-272, doi: 10.1016 / S0370-2693 (98) 00466-3 , arxiv : hep-ph / 9803315 .