How do quantum mechanics and general relativity conflict?
Answers
The definition of time, be it curved or flat, which is quite a fundamental difference indeed.
And so they can’t both be correct interpretations of reality. but simply by amending each of them by making a very simple correction they can be made accurate, compatible and can easily be combined with each other as well as with gravity. I’ve done that myself, it's very simple and embarrassingly easy.
Basically, the only correction that you need to make is accepting that photons interact with electromagnetic fields, - that's it. The rest all follows from that and is almost self-explanatory. And in a nutshell that's the answer to the central mystery of Quantum Mechanics - that of Wave-Particle Duality.
I've written detailed papers about this, though I have not and cannot publish these anywhere official of course as I am not an established Physicist, and I haven't sought to distribute these widely as I'm still intending to add a bit of additional detail still. But you can read and download them at this Dropbox link - GUT
I presume there might be some appeal to being almost the only person ever to have correctly understood the fundamental nature of reality, so please enjoy. You might wish to start with the Relativity section as it's shorter.
Established Physicists however unfortunately refuse to unlearn what they've learned including a few errant fundamental unproven assumptions our current theories were built upon, - including that photons don't interact with anything, (although there is of course plenty of evidence for that including evidence that you can observe yourself with a sensitive photon receptor such as your naked eye).
Take lasers; we use lasers because they produce coherent light; and therefore a laser beam does not spread out. In contrast, the photons in a non-coherent beam of light will interact with each other and cause the light to spread out. So Physicists use lasers in labs every day strictly because the photons from it don't interact, but still will still argue to their deathbed that photons never ever interact. (Rephrased; if photons did not interact then there wouldn’t be any reason to ever have a laser). That takes a level of cognitive dissonance that I cannot begin to fathom, but would anyone wish to take a stab at explaining that??
Explanation:
Off the top of my head, one conflict is between quantum entanglement and relativity, though this conflict has been "explained away" in a sense.
Two objects are entangled if knowing information about one object allows you to know information about a second object, which you have not made a direct measurement of.
Quantum mechanics says that if the state of an object/particle is unknown, before a measurement is made, the object simultaneously possesses all possible values for that measurement. When a measurement is made, the superposition state is disturbed, the wave function collapses, and a single value/property is observed.
Quantum entanglement says that if two objects are entangled and a measurement of the state of one of the objects is made, the wave function of the first object collapses from the superposition of states to a single possibility, which causes the wave function of the entangled object to collapse as well, giving both objects "definite" properties when only one of the objects was measured. This implies that the objects are "communicating" in a sense.
Einstein tried to use this notion to disprove QM by devising a thought experiment which, in essense, said that if you took two entangled objects to opposite sides of the universe and made a measurement of one, somehow that object would have to send information to the other object and tell it which state it needed to assume. If you had your friend on the opposite side of the universe make a measurement of one of the entangled objects a split second after you did, that information would have to travel an unfathomably large distance in a very small amount of time, i.e. faster than the speed of light (EPR paradox). This directly violates Einstein's theory of relativity.
However, the no-communication theorem proposed that QM does not actually result in a paradox, and relativity is not violated there.
This is just one example; there are other reasons why QM and relativity do not get along so well.