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Foreword But, little by little, it was realized that causal - or Time - loops can appear in other solutions of Einstein equations as well - usually they correspond to some kind of “rotation” of the universe. Causal loops make time travel not only possible, but probable. But then, causal loops lead to unacceptable logical paradoxes, and physics does not like such paradoxes at all - they are a serious problem! But, the subject of communicating with the past or receiving information from the future IS being discussed in physics even in terms of the flat, not-curved-at-all space-time of Lorentz and Minkowski. Hypothetical faster-than-light particles - tachyons - can serve as the communication means. They make an “anti-telephone” - a telephone for some. And, the truth is that paradoxes must never be ignored. They always indicate that some important lesson is to be learned; that some essential improvement or change is necessary. The same holds true for the paradoxes involved in the idea of receiving information from the future. We cannot simply go back into Saturday and tell ourselves the winning lottery numbers of Sunday. If this were possible, then it should also be possible for some future, future self to tell a future self vot to tell! Thus A paradox: if we communicated, we have not communicated, and if we do not communicate, then we have communicated! Impossible in a Is there a possible escape from the paradox, an escape that leaves a door open, even if only a little - for our anti-telephone? First of all - the evident paradox disappears if we admit the possibility that the communication channels are inherently noisy; that is a normal situation when we deal with quantum phenomena. So, if the communication into the past is a quantum effect - we are saved from situation when deal with So, if the we Sending a signal into the past, we are never 100% sure if the message will be delivered without distortion. And conversely, receiving info from the future we are never 100% sure if this comes from an authentic broadcast or is a spontaneous and random creation of the receiving end. If this is the case, and if certain quantitative, information - that is, into the past - possible. But do tachyons exist? Or can they exist? Well, that is still a question that has not been answered definitively we have a paradox: we, in the future, have intervened into the past making our communication from the future impossible! linear, non-branching universe! Indeed, there is, and not just one, but several ways out. evident paradoxes. Quantum Theory can be useful!