0

We know and have actually measured in the lab with self-interference neutron experiments the 4π-symmetry (720° rotation Dirac Belt characteristic) of all spin-1/2 particles (except the neutrinos) thus the charged fermions.

Also we know that all normal Bosons like photons are spin-1 particles and therefore have a normal 2π-symmetry (360° rotation characteristic).

But what about the theorized spin-2 graviton particle?

By deduction the spin-2 corresponds to a π-symmetry (180° rotation characteristic) for the graviton.

But this would require in order to be observed in the lab frame due to relativistic Thomas precession a Lorentz factor:

$$ \gamma=\frac{1}{2}<1 $$

Therefore, a $γ$ value less than $1$ which is not allowed by Special Relativity since this would result to a $x2$ "time contraction" instead of time dilation thus superluminal behavior!

The above makes relativistic impossible of such a spin-2 particle to ever exist and in general the spin-2 theorized characteristic.

What I am doing wrong here? I'm confused.

Qmechanic
  • 201,751
Markoul11
  • 3,853
  • It's $2\pi$ for bosons of any spin and $4\pi$ for fermions of any spin. – Connor Behan Apr 01 '23 at 13:41
  • 3
    Related (not duplicate): https://physics.stackexchange.com/q/70718/226902 and this answer: https://physics.stackexchange.com/a/4/226902 . About the 180 degrees: https://physics.stackexchange.com/q/31317/226902 – Quillo Apr 01 '23 at 13:57
  • 1
    Related: https://physics.stackexchange.com/q/597902/2451 and links therein. – Qmechanic Apr 01 '23 at 14:04
  • @ConnorBehan Quote: "It's 2π for bosons of any spin". Yes this is true also for a spin-2 Boson particle as well as for a spin-1 Boson but you forgot to mention a "small" detail which is that a spin-2 particle will come back to its initial state for a 2π rotation, twice! Therefore fundamentally, the spin-2 particle has a π-symmetry and not a 2π-symmetry a spin-1 particle has. Thus, IMO these two are fundamentally different. – Markoul11 Apr 01 '23 at 18:13
  • I don't think my question here is duplicate since the description in this question also asks about implications with SR of the theorized spin-2 graviton? In particular I ask if a rotational π-symmetry massless particle would violate SR? – Markoul11 Apr 01 '23 at 18:42

0 Answers0