# A simple question about relativistic quantum mechanics

**URL:** <https://boards.straightdope.com/t/a-simple-question-about-relativistic-quantum-mechanics/196903>\
**Category:** Factual Questions\
**Created:** [August 22, 2003, 12:25pm UTC](https://boards.straightdope.com/t/a-simple-question-about-relativistic-quantum-mechanics/196903 "2003-08-22T12:25:25Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Skeptico](https://avatars.discourse-cdn.com/v4/letter/s/e19b73/32.png) [@Skeptico](https://boards.straightdope.com/u/Skeptico)\
**Post date:** [August 22, 2003, 12:25pm UTC](https://boards.straightdope.com/t/a-simple-question-about-relativistic-quantum-mechanics/196903/1 "2003-08-22T12:25:25Z")

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There seems to be many books on Relativistic Quantum Mechanics (I’ve never read them), however, I seem to remember from Brian Greene’s “Elegant Universe” that QM and relativity theory were incompatible. How do RQM books solve the locality problem? What am I missing here??

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**Author:** ![MC\_Master\_of\_Ceremonies](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)\
**Post date:** [August 22, 2003, 1:24pm UTC](https://boards.straightdope.com/t/a-simple-question-about-relativistic-quantum-mechanics/196903/2 "2003-08-22T13:24:59Z")

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QM and relativity as a whole are incompatible, but QM and special relativity are not. Dirac formulated the Dirac equation in 1928 and it’s essientally a relativistically corrected version of the Schroedinger equation.

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [August 22, 2003, 1:33pm UTC](https://boards.straightdope.com/t/a-simple-question-about-relativistic-quantum-mechanics/196903/3 "2003-08-22T13:33:34Z")

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Superstring theory and more recently, M-theory go a long way towards uniting QM and General Relativity. Especially under the overarching construct of M-theory, which incorporates string-based 11-dimensional supergravity, this new way of thinking about the universe doesn’t merely explain gravity, but _requires_ it, something no previous theory had done. This is very well explained in the last half of _The Elegant Universe_. As far as the mathematics behind it, don’t ask me.

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**Author:** ![Keeve](https://avatars.discourse-cdn.com/v4/letter/k/f07891/32.png) [@Keeve](https://boards.straightdope.com/u/Keeve)\
**Post date:** [August 22, 2003, 1:55pm UTC](https://boards.straightdope.com/t/a-simple-question-about-relativistic-quantum-mechanics/196903/4 "2003-08-22T13:55:00Z")

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> [@](#):
>
> \*Originally posted by Skeptico \*  
> \*\*There seems to be many books on Relativistic Quantum Mechanics (I’ve never read them), however, I seem to remember from Brian Greene’s “Elegant Universe” that QM and relativity theory were incompatible. How do RQM books solve the locality problem? What am I missing here?? \*\*

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**Author:** ![RM\_Mentock](https://avatars.discourse-cdn.com/v4/letter/r/e274bd/32.png) [@RM\_Mentock](https://boards.straightdope.com/u/RM_Mentock)\
**Post date:** [August 22, 2003, 2:34pm UTC](https://boards.straightdope.com/t/a-simple-question-about-relativistic-quantum-mechanics/196903/5 "2003-08-22T14:34:09Z")

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> [@](#):
>
> \*Originally posted by Skeptico \*  
> \*\*How do RQM books solve the locality problem? What am I missing here?? \*\*

What MC said. Plus, the modern view is that space time can be viewed as locally flat–that is, compatible with special relativity. That’s the relativity of “relativistic quantum mechanics.”