Modern centrifuges are improved a lot from the last time their record values were published. Magazine "Popular mechanics) back in 1950 (70 years ago) was already mentioning centrifuges with 166000 rotations per second [1]. Assuming the scientific progress continued today they are even faster. Since from equivalence principle of Einstein the accelerated motion of the object (including atom or molecule) is the same as the motion in gravitational field, such ultracentrifuge may be helpful in discovering and verifications of the new quantum phenomena connected with the gravity.
Most theories talking about the gravity on atomic level are mentioning the vicinity of black hole or neutron star, but modern centrifuges may offer the same accelerations on Earth. For example, even biological centrifuges may easily reach 1 millions g (which is enough for separation of any proteins), but they are not intended for physical experiments and probably the specially made centrifuge may go much further.
There are several possible phenomena relevant for such gravitational force.
1.Deviation of slow light.
The hypothesis that the slow light deviates much stronger inside the stars and may thus generate the gravity force in addition to the usual gravity of baryonic matter is expressed in [2]. However, the deviation of the light in the usual gravity is too weak to be measured directly for light in refracting matter (in the vacuum it was measured during Einstein times and is the confirmation of general theory of relativity). Using the same approach as in [2], for the deviation of light in any weak (compare to the inside of the black hole) it is twice as strong as Newton deviation. For example, for the deviation of the light which travels with the velocity of 0.7c (for example, inside the glass) the formula would be as follows.
For the distance of L=1 meter (reasonably long centrifuge) the time of travel would be:
t=L/(0.7*c)
here t is the time of travel, c is speed of light in vacuum.
Deviation in the perpendicular direction (assuming the light is traveling almost along the axis of the rotation, in uniform gravitational field):
S=a*t*t (this would be twice the Newtonian value of a*t*t/2)
The angle would be:
a=S/L=a*L/(0.49*c*c)=2.3*10exp(-10)
for a equal to 1 million g. The shift for light S is only 2.3 A - too small to be measured easily.
For easy to notice deviation of say 1 mm the velocity of light should be 100000 m/c (or 0.00033*c).
Today the experiments exists for light as slow as 90 m/c [3], so the experiment of observation of slow light will not even need the record centrifuge.
2.Ionization induced by the gravitational field.
In strong enough electric field the tunneling of the electron out of the molecule happened. This called field ionization and usually needs rather high electric field. The observation of the phenomena close to field ionization using the gravitational field may be only possible for the molecules or atoms which are already close to being ionized - excited atoms or molecules, where the electron is in Rydberg state for atoms in vacuum or in Rydberg like state in semiconductors.
Rydberg atoms are capable of detection of the microwaves with frequencies in MHz range already [4](pre-excited by laser atom enters the Rydberg state and gets the final energy from RF quanta). For 100 MHz the energy of quanta is only 4.1*10exp(-7) eV
The idea is that such Rydberg atom being placed in a strong gravitational field (say 10 millions g) will create the potential bending for electron shallow enough to observe the tunneling of electron out of such an atom.
The largest problem to obtain even more excited states Rydberg states is temperature (electron should be on the Rydberg level at least around kT from ionization barrier. For record temperatures achieved on the level of 50 nK that means that the lowest energy detection possible for Rydberg atom hold at this temperature is kT, 6.9*10exp(-31) Joule or 4.3*10exp(-12) eV (assumed it is hold near the thermal bath big enough to absorb the heat created at laser excitation to the Rydberg level)
For the gravitational field of 10 millions g the energy of E=6.9*10exp(-31) J is reached at the distance of:
L=E/F=E/(m*10exp(7)*g)=7.7*10exp(-9) m
So electron should tunnel only 7 nm under barrier to reach the space where it may escape Rydberg atom. This value is a reasonable distance for tunneling of electron (up to 100 Angstroms).
Therefore, such experiment is already at the reach of the modern physics.
The largest problem of the observation of such phenomenon would be the ionization of the material induced by stress (mechanochemistry). Indeed, the gravitational field of 10 millions g is smashing any material very perceptibly. As the huge stress is build inside, the electrons will be emitted merely because near the defects they will be excited enough to leave the material even without help of gravitational pull on the electron itself [6]
Careful choice of materials, long waiting time (conditioning) and modulation of laser beam creating the Rydberg atoms may allow to overcome this problem
References.
1."Merry-go-round of industry"// Popular Mechanics, 1950, January, p. 147
2.https://tipikin.blogspot.com/2019/11/weak-equivalence-principle-is-not-valid.html
3.https://physics.aps.org/story/v3/st37
4. https://arxiv.org/abs/1808.08589
5. https://phys.org/news/2019-02-coldest-quantum-gas-molecules.html
6. https://onlinelibrary.wiley.com/doi/abs/10.1002/masy.19910410105
V.A.Zakrevskii "Electron emission during deformation of polymers"
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