Traditional Newtonian physics cannot explain many observed galacticscale gravitational effects and phenomena. This has led to many new theories, but most cannot explain all phenomena simultaneously. This is shown in Table 1.
One such theory is Dark Matter. The current theory suggesting that Dark Matter is comprised of tiny particles is generally accepted; however, this theory faces some tough challenges such as the TullyFisher Relation and the CoreCusp Problem. To date, no such particle has been detected after more than three decades of research.
Due to the obvious problems with the above Dark Matter theory, some alternatives have been proposed. One of them is the MOND (Modified Newtonian dynamics) theory, which can explain some observations neatly, but this theory is also struggling with some other observations, such as the Bullet Cluster, Gravitational Lensing, CMB, and expansion of the universe.
In 2020, a new unified field theory on gravity was published that can explain all the above phenomenon [1,2]. The new field theory postulates that if gravity forces are due to an elastic field, it would also be exerted by electromagnetic waves or photons of light. According to this new theory, this is where the extra gravity force on those socalled Dark Matter observations comes from. The equations for the new force are as follows:
(Gravity force between photon and photon)
(Gravity force between photon and object with mass)
Where:
F – gravity force between two photons or between a photon and an object with mass (N)
Y1 = 3.61 × 10^{−111} 𝑚^{3} 𝑘g
Y2 = 4.91 × 10^{61} m^{3} s^{1}
k – number of photons of the same frequency
f – photon frequency (Hz)
m – mass of object (kg)
r – distance between object with mass and photon (m)
Table 1 Comparison of Different Theories on Phenomenon Each can Explain

Dark Matter

MOND

Gravity by EM waves

Galaxy Rotation Curve

Yes

Yes

Yes

Gravitational Lensing

Yes

No

Yes

Bullet Cluster

Yes

No

Yes

TullyFisher Relation

No

Yes

Yes

Dark Matter Halo

No

No

Yes

CoreCusp problem

No

Yes

Yes

Data on Cosmological scale

Yes

No

Yes

Under Process (Review Completed)