Yes, that has been the holy grail of modern physics for the last 40-50 years. The reason is because we are discovering that our Universe is not what it superficially appears to be, i.e. normal matter is only a paltry 4% of the matter/energy density in the Universe. The rest is made up of dark matter, 22% and dark energy, 74%. they are called dark because we have NO idea what they are. And on top of that, our current physical theories breaks down at extremely high energies (or high temperatures) and very small distance scales. Einstein worked on this problem until his death without success, and right now many physicists are working on it as well, but so far we have not come up with anything definitive. But the contenders for this new theory to explain how the Universe really works are:
Superstring Theory, Supergravity, and Loop Quantum Gravity.