How could Doug Carlin possibly go through time without getting completely mangled?

Question

I have watched this sci-fi thriller Deja Vu almost 10 times and could not get one thing.

Denny (Adam Goldberg) explains to Doug (Denzel Washington) about the machine which was under the workshop that it worked on the principle of Einstein-Rosenberg bridge which made it possible for them to devise an algorithm to look 4 days 6 hours ago into the past.

He further explained that they created instantaneous link between two distinct points using huge amounts of energy; an amount of energy that could black out approx. 50 million homes.

After that they send a piece of note to the Agent Minuti's office. Now, my question is: how could that piece of paper survive the passing through that bridge using such a tremendous amount of energy, let alone Mr. Doug Carlin in the last few minutes of the movie?

OK, he was shown having a seizure after that time travel but seriously, things could have or I should rather say should have been much worse. Isn't it?

Answer 1

The operative phrase is "works on the principle" of the Einstein-Rosen bridge. Since the movie was short on the mechanics, we can only use what we have seen as a reference.

• The trip through time connects the two locations across time, an unlikely but theoretically possible application of the physics (the two locations are space coordinates separated by time).

• The portal accommodates the movement of matter from one location to another, apparently without changing its state or condition except in the case of living beings whose "electromagnetic" systems (heart, brain) shut down and required immediate resuscitation.

• The scientists had only limited experience with sending living things through and could not reliably judge what possible effects (besides the death of the subject) could happen.

What else can be inferred by the movie?

• The "bridge" could only create a portal between two visible locations, so they had to be able to be watching the location for a portal to be opened there.

• The object transferred could not be alive. If it was, it would experience failure upon arrival. (The mechanics are left sketchy, but time travel Doug didn't seem to be in the best of health after resuscitation.) Nor does he live long enough for us to determine whether he and his other temporal self could co-exist.

• The energy required to open the bridge was fantastic.

We are left to assume:

• mass is not an issue since the portal moved anything able to be fit within the chamber. It is safe to assume the scientists considered sending people, since they made it just large enough to fit a person. What they lacked was a willing (to potentially die) subject.

• the connection to the past appears paradox-resolving, since anything sent to the past immediately effects that past in real time. Hence the other investigator meeting his untimely end after reading the "pushed" message.

• Please note: the Future Doug dies an untimely death, so I consider this a very tidy universe as far as temporal paradox goes.

Answer 2

The energy isn't used to send things back, it's needed to keep the wormhole open while you send things back. A stable wormhole mouth requires negative energy density around the hole. The more positive energy passing through the hole (photons, matter) the more negative energy you need to compensate to keep the wormhole from collapsing. So Doug Carlin survived the trip because the tremendous energies involved were not flowing through him. Rather, all of the energy was going toward holding the wormhole open while Carlin passed through it.

(Don't ask me how they create a negative energy density with positive energy from the electrical grid... my hands can't wave that fast.)