Solution for the “Grandfather Paradox”?

One theory suggests that this problem might be be preventable before you travel through time in the first place:

The model of time travel proposed by Seth Lloyd, et al., in a recent paper at arises from their investigation of the quantum mechanics of closed timelike curves (CTCs) and search for a theory of gravity. In simple terms, a CTC is a path of spacetime that returns to its starting point. The existence of CTCs is allowed by Einstein’s general relativity, although it was Gödel who first discovered them. As with other implications of his theories, Einstein was a bit disturbed by CTCs.
In the new paper, the scientists explore a particular version of CTCs based on combining quantum teleportation with post-selection, resulting in a theory of post-selected CTCs (P-CTCs). In quantum teleportation, quantum states are entangled so that one state can be transmitted to the other in a different location. The scientists then applied the concept of post-selection, which is the ability to make a computation automatically accept only certain results and disregard others. In this way, post-selection could ensure that only a certain type of state can be teleported. The states that “qualify” to be teleported are those that have been post-selected to be self-consistent prior to being teleported. Only after it has been identified and approved can the state be teleported, so that, in effect, the state is traveling back in time. Under these conditions, time travel could only occur in a self-consistent, non-paradoxical way.

There is also the theory that there was never a problem to begin with as covered in the video below.

Thanks to for the great info



  1. Rodrigo Peres Triana said:

    If anybody is capable to return by the same spacetime way he came from, everything will be different. The individual will live a different life, since the Energy-Space interactions will never repeat equally, every single interaction between these opposites is different. THE ORIGIN OF TIME AND OUR UNIVERSE

    The origin of Time and the Universe are strictly linked to the dialectic relationship of Energy and Space. The hypothesis that I propose is as follows: These two ‘basic’ elements (Energy and Space) have existed for ever, before our Universe was ‘created’. They will never disappear…

    Energy and Space can not be separated ever, imagin that every matter particle o its energetic manifestation were somehow removed of any volume of Space, it would be impossible to eliminate out of it the Casimir forces or the appearance of virtual particles, in other words Energy is intimately married to Space’s quantum fields.

    Matter particles are in reality the excitation of quantum fields and even virtual particles are also excitation of such fields, but of very briefly existence. Matter is just Space excited by Energy…

    If anything could travel at light speed, time for that thing would freeze, stop…
    My proposition is that before the emergence of our Universe, all Energy was interacting with Space at Light speed, Time was frozen, Eternity was present. Somehow, by a casual move or quantum change, Energy pockets slowed down its interactions with Space, emerging sudenly,Time and its relative variations.

    The new interaccions of Enegy with Space at different conditions and speeds, Multivers emerged with their own physical laws and different multitud of characteristics. Ours was, probably the one with those physical laws that permited the creation of suitable conditions for live, etc…

  2. David Hua Ken Cheng said:

    In quantum entanglement theory one can simultaneously be in many places at the same time. If you travelled back to the past and killed your younger self – there will be many more of you – each with different properties – virtually existing somewhere else.

  3. Ed Sigward said:

    You can’t go back in time and kill your grandfather, because that is in the past and has already happened, the proof is that you are alive and reading this.