Saturday, February 17, 2007

Universal Feast

Photo thanks to Jimmy James @ Under The Ledge click image to enlarge

Logic would dictate that just as there is space time, there is Space outside TIME.

In spacetime we can take a snapshot and freeze time, we can even rewind a film on video or dvd, but we do this travelling forward thru time. Even when we look at the distant stars and galaxies in the universe, we are looking at the light that reaches us on Earth, from a time long past.
[+/-] Click here to expand

Time (and even Space) as we shall see is relative to the observer, and as humans we are travelling thru time (and ageing over time).

It is movement that creates the impermanence of time, but there must be a Space outside Time where motion (or movement) is possible without decay, ageing, disease, suffering or death - among the multiverses that Leonard Susskind & Alex Vilenkin would like us to be aware of (see or imagine) - they seem to have ommited the one Above All where Time itself does not exist.

Just for a moment imagine yourself looking at a film of yourself on a 2D or 3D screen, now take a further step back and look at yourself in 3D+T (from outside Time).


Stephen Hawking has worked on the basic laws which govern the universe. With Roger Penrose he showed that Einstein's General Theory of Relativity implied space and time would have a beginning in the Big Bang and an end in black holes.

These results indicated it was necessary to unify General Relativity with Quantum Theory, the other great Scientific development of the first half of the 20th Century. One consequence of such a unification that he discovered was that black holes should not be completely black, but should emit radiation and eventually evaporate and disappear.

Another conjecture is that the universe has no edge or boundary in imaginary time. This would imply that the way the universe began can be completely determined by the laws of science.

Stephen Hawking

We live in the aftermath of a great explosion. This awesome event, called somewhat frivolously the big bang, took place about 14 billion years ago. We can actually see some of the cosmic history unfolding before us since that moment—light from remote galaxies takes billions of years to reach our telescopes on earth, so we can see galaxies as they were in their youth.

But there is a limit to how far we can see into space. Our horizon is set by the maximum distance light could have traveled since the big bang. Sources more distant than the horizon cannot be observed, simply because their light has not yet had time to reach Earth.

And if there are parts of the universe we cannot detect, who can resist wondering what they look like? Until recently physicists thought that the answer to this question is rather boring: it’s just more of the same – more galaxies, more stars. But now, recent developments in cosmology have led to a drastic revision of that view.

According to the new picture, distant parts of the universe are in the state of explosive, accelerated expansion, called “inflation”. The expansion is so fast that in a tiny fraction of a second a region the size of an atom is blown to dimensions much greater than the entire currently observable universe. The expansion is caused by a peculiar form of matter, called “false vacuum”, which produces a strong repulsive force.

The word “false” refers to the fact that, unlike the normal “true” vacuum, this type of vacuum is unstable and typically decays after a brief period of time, releasing a large amount of energy. The energy ignites a hot fireball of particles and radiation. This is what happened in our cosmic neighborhood 14 billion years ago – the event we refer to as the big bang.

With inflation, the two competing processes are the decay of the false vacuum and its “reproduction” by rapid expansion of the inflating regions. My calculations, and those of Andrei Linde, show that false-vacuum regions multiply much faster than they decay, and thus their volume grows without bound.

At this very moment, some distant parts of the universe are undergoing exponential inflationary expansion. Other regions like ours, where inflation has ended, are also constantly being produced. They form “island universes” in the inflating sea of false vacuum. Because of inflation, the space between the islands rapidly expands, making room for more island universes to form.

Inflation is thus a runaway process that has stopped in our neighborhood, but still continues in other parts of the universe, causing them to expand at a furious rate and constantly spawning new island universes like our own. This never ending process is referred to as “eternal inflation”.

The role of the big bang in this scenario is played by the decay of the false vacuum. It is no longer a one-time event in our past: multiple bangs went off before it in remote parts of the universe, and countless others will erupt elsewhere in the future.

Analysis shows that the boundaries of island universes expand faster than the speed of light. (Einstein’s ban on super-luminal speeds applies to material bodies, but not to geometric entities such as the boundary of an island.) It follows that, regrettably, we will never be able to travel to another island, or even send a message there. Other island universes are unobservable, even in principle.

In the global view of eternal inflation, the boundaries of island universes are the regions where big bangs are happening right now. Newly formed islands are microscopically small, but they grow without limit as they get older. Central parts of large island universes are very old: big bangs once took place there long time ago. Now they are dark and barren: all stars have long since died there. But regions at the periphery of the islands are new and must be teeming with shining stars.

The inhabitants of island universes, like us, see a different picture. They do not perceive their universe as a finite island. For them it appears as a self-contained, infinite universe. That dramatic difference in perspective is a consequence of the differences imposed by the ways of keeping time appropriate to the global and internal views of the island universe. (According to Einstein's theory of relativity, time is not fixed, but instead is observer dependent.)

Perhaps the easiest way to see this is to count galaxies. In the global view, new galaxies are continually formed near the expanding boundaries, so as time passes, we have an infinite number of galaxies in the limit. In the internal view, all this infinity of galaxies exists simultaneously (say, at time 14 billion years). The implications are extraordinary.

Since each island universe is infinite from the viewpoint of its inhabitants, it can be divided into an infinite number of regions having the same size as our own observable region. My collaborator Jaume Garriga and I call them O-regions for short. As it happens, the most distant objects visible from Earth are about 40 billion light-years away, so the diameter of our own O-region is twice that number.

Quantum fluctuations in the course of eternal inflation ensure that all possible values of the constants are realized somewhere in the universe. As a result, remote regions of the universe may drastically differ in their properties from our observable region. The values of the constants in our vicinity are determined partly by chance and partly by how suitable they are for the evolution of life. The latter effect is called anthropic selection.

Another recent application of the principle of mediocrity, unrelated to string theory, is to the amount of dark matter in the universe. As its name suggests, dark matter cannot be seen directly, but its presence is manifested by the gravitational pull it exerts on visible objects. The composition of dark matter is unknown. One of the best motivated hypotheses is that it is made up of very light particles called axions. The density of axionic dark matter is set by quantum fluctuations during inflation and varies from one place in the universe to another.

Alex Vilenkin

However, it is clear that just as photons can be in many possible places but are only actually in one, we as humans though we can potentially be in many places are only actually ever in one, and that one place will be wherever we happen to be in 1) our physical body, and 2) our mind or mental state.

All our other states in Vilenkin's multiverses are effectively or conceptually in a different time frame, or outside Time - but they are unlikely to be at the same time. After all we can talk to many people in an auditorium or through tv, but we can only ever hold a one to one with one person at a time, and a dialogue or conversation with a few at most - even during video conferencing.

The multiverse is like a flower from Dialogues of Eide
Quantum Phase Transitions from Science Daily releases
Universe offers 'eternal feast' by

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