å Kurt Sanders

Thursday, March 12, 2009

The Impossible Takes Longer!

Type 1 impossibilities

  • Impossible today, but do not violate the known laws of physics. Might be possible this decade or the next: force fields, invisibility, teleportation, telepathy, robots capable of self awareness, antimatter and traveling through worm holes

Type 2 impossibilities

  • Technologies that sit at the edge of our understanding of the physical world. May be realised century or of years in the future: faster-than-light travel, muli-dimensional time travel, parallel universes, 5th dimension, elimination/reversal of aging.

Type 3 impossibilities

  • Technologies that violate the known laws of physics. If they turn out to be possible, they would represent a fundamental shift in our understanding of physics: perpetual motion machines, precognition, serial time branches

per Michio Kaku's ratings

Wednesday, March 11, 2009

Time Travel & Teleportation

There is actually nothing in the laws of physics that prevents moving in time, which would support Teleportation. The way it works is to take a trip through a worm hole connecting one point in space and time with another. The laws of physics suggest that the intense gravity of a black hole is enough to rip the fabric of space and time, making a worm hole possible where one moves in time, not forward or backward.

A unexpected side effect to moving in time is the creation of an metamaterial which eliminates reflections and shadows, and renders an object invisible.

Sunday, February 22, 2009

Time Travel Paradox

Time travel is a immensely fascinating topic and can be discussed with friends & family for an infinite amount of time. For purposes of this blog, I will introduce "Time Branches"

Suppose a person travels to a historical time before they were born and breaks the event that led to the traveler's birth. This problem has been commonly explored by asking 'What if one kills their own father's mother before she first conceived your father?' The apparent paradox is then of a logical sort:
  • X forces NOT X and NOT X forces X.
If one kills their father's mother then one would not be born, which in turn would bring it about that one not travel into the past, thus one would not kill ones' father's mother, thus one would be born causing one to again travel into the past to kill ones' father's mother....
  • Thus the "Ad Infinitum" endless loop.
The presupposition of almost all time travel stories is that each point along a time line is in some sense existent now, even the future points. This provides a conceptual basis for allowing us to visit a time point in the same way that we might visit a space point in ordinary experience. Einstein may have reinforced our comfort with this view by taking seriously the notion of time as another dimension very much like the spatial dimensions we are already familiar with.

Some stories entertain the notion that you can go back and change things, but not those things that would lead to paradox. I would like to put forth the view that there is something wrong with all of these approaches and that the only view which is successful at resolving the paradox is an alternate universe theory of time travel which we shall explore momentarily. Such a view was expressed in "The Terminator" in which a character from the "future" confesses that maybe he just comes from a "possible future " not the actual future of this time.

When a time travel event occurs, it is helpful to see that it may be one of two kinds. Take, for instance, a "traveling" from time point c to time point b, where c is later than b. Either we are sending an object to a time and place where it already was and it is the same object in every respect as that object in that time and place or we are sending it to a place that it wasn't or at least wasn't in that exact state. Let us consider the second possibility first.

Supposing that the object wasn't at b but we intend to send it there anyway. If we are successful then we have created a contradiction, for it becomes clear that when the time travel event occurs it becomes true that the object was at time point b and yet it was false that the object was at b. This is an impossibility if we take any standard linear view of time. The most minimal means to accommodate this contradiction is to allow a timeline where the statement that the object exists at b is true and another timeline where the statement that the object exists there is false (the 'original' timeline.). In other words a timeline branching event has occurred. Any story that holds that the object was not on the timeline and now it is, is minimally committed to this branching universe concept. See Figure A...