The question is not if we are going to colonize Mars, but rather when.
7 months of travel in zero-gravity is really an easy problem. There are much more difficult problems. I would compare this problem with the problem of colonizing America by Europeans, 1000 years ago. It was very difficult. It was possible, but difficult. Vikings settled America 1000 years ago, but it was so difficult, that their colonies died shortly, and the colonization failed. But it was done 500 years later by their descendants, which had developed significantly better technology by then.
Asimov came up with a great aphorism: it is sufficient to know that something is possible, to be able to do it. Knowing that something is possible is sufficient to start working on the task; and then it is only a matter of time and resources to achieve the task. He was actually referring to hyperspace travel.
By the way: we now know that hyperspace travel is possible. So, someday we will have it - in 5, 10 or 200 years, but we will have it, because it was already proven to exist.
Interestingly, we now do NOT know if artificial intelligence/the singularity is possible!
Referring to quantum teleportation: there were already 3 successful teleportation tests using entanglement in the last years. None of them are conclusive, and entanglement is still surrounded by weird paradoxes, but there is something, and it's working.
- The Chinese did a couple of experiments, with the cave and the moon was one, in 2017.
- Here is the more recent American experiment - they actually seem to control it already.
The theoretical basis is of course entanglement. The theory that 2 particles that become entangled maintain the same spin or other quantum state, irrespective of their physical distance.
The weird paradoxes are that it seems that you cannot set or change the quantum state, without affecting the entanglement; and the observer paradox (related to Schrodinger): there is no state until you look at it; and you cannot look at it without changing it, and we don't even know how it changes when we look at it. So we really don't know very well how to control the phenomenon. But the experiments are getting better at it.
It's like when we discovered fire: it was new and smart and seemed very intelligent, buy nobody really knew how to control it or what to do with it.
I understand very little of quantum physics, really; but I find all this fascinating. And much more fascinating is that this whole stuff seems to be working - which is somehow the way all scientific breakthroughs have always occurred. A mix of weird successful experiments plus weird theoretical explanations that somehow seem to work together, and in the end what comes out is very practical things, like wifi, or radio, or laser, or - well - now we're playing with something that seems to be beyond and/or outside Einstein's limit for the speed of light, and this new thing needs a new theory, and physicists have been trying to explain this with quantum, entanglement, and string theories. But the mix is kind of working. So, yeah, I think there is already a breakthrough that is currently only being expanded.
Quantum teleportation of information is already proven. This is huge, because it means talking instantaneously with any space craft, no matter the distance. What researchers are working on , is to make it efficient.
The next question will be - and this is much more complicated - how to teleport matter. Not easy. Even if we can imagine that it should use the same principles, in practice it could take hundreds of years to perfect such technology. It is probably much more difficult than the jump from proving electromagnetic waves, to achieving virtual 3d reality :) But that was only a matter of resources, and using the same technology and theory. Now, we have the quantum theory - so it is only a matter of time and resources to develop full teleportation technology.