Conserved quantity due to invariance under temporal rotations

In summary, the conversation discusses the use of Noether's Theorem to determine conserved quantities in the context of the so(3,3) Lie algebra. It is noted that invariance under temporal and spatial rotations both lead to conserved quantities with units of Planck's constant, which may suggest the existence of a second type of spinor representation. The conversation is continued in a separate thread.
  • #1
Marty4691
20
1
Hi,

I was looking at the so(3,3) Lie algebra which has 3 temporal rotation generators as well as the normal 3 spatial rotation generators. When I try to use Noether's Theorem to determine what the conserved quantity is, due to invariance under temporal rotations, I seem to get an integral where the integrand is of the form

[(energy)*(time) - (energy)*(time)]

The equivalent integrand corresponding to spatial rotations is

[(momentum)*(distance) - (momentum)*(distance)]

which is normal because the conserved quantity turns out to be angular momentum. But (energy)*(time) has the same units as angular momentum which seems to imply that invariance under temporal rotations and invariance under spatial rotations both lead to conserved quantities with the units of Planck's constant. I'm not sure if this can be right.

My calculations are on the back of an envelope so I was hoping that someone might know if this is correct or if there is a paper that deals more rigorously with this question.

Thanks.
 
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  • #2
Marty4691 said:
But (energy)*(time) has the same units as angular momentum which seems to imply that invariance under temporal rotations and invariance under spatial rotations both lead to conserved quantities with the units of Planck's constant. I'm not sure if this can be right.
Why would this be an issue?
 
  • #3
In the context of so(3,3), if the above is correct then there might be a second type of "spinor" representation. The normal spinor representation has the form

{(J+iK), (J+iK), (J+iK)}

where the Js are spatial rotation generators and the Ks are boost generators. The second type of representation would have the form

{(T+iK), (T+iK), (T+iK)}

where the Ts are temporal rotation generators.

It might open the door to an additional mathematical description for a spin 1/2 particle.
 

FAQ: Conserved quantity due to invariance under temporal rotations

1. What is a conserved quantity due to invariance under temporal rotations?

A conserved quantity due to invariance under temporal rotations is a physical quantity that remains constant over time when the system is rotated around its axis. This means that the laws of physics governing the system do not change when the system is rotated, leading to the conservation of certain quantities.

2. How does invariance under temporal rotations lead to conservation?

Invariance under temporal rotations means that the laws of physics governing a system do not change over time. This leads to the conservation of certain quantities because the system's behavior remains the same, and therefore the same physical quantities are conserved over time.

3. Can you give an example of a conserved quantity due to invariance under temporal rotations?

One example of a conserved quantity due to invariance under temporal rotations is angular momentum. This is because the laws of physics governing rotational motion do not change over time, and therefore the angular momentum of a rotating system remains constant.

4. How is invariance under temporal rotations related to symmetry?

Invariance under temporal rotations is related to symmetry because it is a type of symmetry in physics. Symmetry refers to the invariance of physical laws under certain transformations, such as rotations or translations. Invariance under temporal rotations means that the laws of physics governing a system do not change when the system is rotated around its axis, making it a type of symmetry.

5. What are the implications of conserved quantities due to invariance under temporal rotations?

The implications of conserved quantities due to invariance under temporal rotations are significant in physics. They allow us to make predictions about the behavior of a system over time, and they also provide important insights into the underlying laws of physics. Additionally, the conservation of certain quantities due to invariance under temporal rotations is a fundamental principle in many areas of physics, such as classical mechanics and quantum mechanics.

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