**Author:**

(1) Andrew Knight, J.D. (aknight@alum.mit.edu).

## Table of Links

## VI. CONCLUSION

When we assume that zero change to the past implies zero change to the present, we impose the information structure of the present universe onto its past structure – that is, we assume that everything will turn out the same, except for those events (and their chaotic interactions) that were changed in the past. Unfortunately for aspiring time travelers, this notion is false.

Traveling into the past logically requires changing the present, no matter how careful one is to avoid a temporal paradox. Hopes to travel into the past without changing the present, such as by avoiding any physical interaction within the past, are unfounded. Because all serious proposals for time travel into the past inherently assume Eq. 1, which has been shown false on a priori logical grounds, their treatment as scientific proposals are pseudoscientific.

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