Do you believe in gravity?

[numinus]

Try looking at Linde's theories. Who knows if he is accurate, let alone correct. But at least there are a number of theories including his that take away the "sting" out of singularities and nothingness.

He replaced nothingness by an infinite regress.

Hmmmm.

 

[Lagboltz]

I assume you are using the word 'potential energy' as an analogy to the tensile tendency of lambda on space-time geometry.

No, I don't mean lambda. I sent you a reference on that a while ago. Mass energy is roughly equal to the gravitational potential energy.

By disappearing, do you mean being annihilated or being converted into something else entirely?

No. Disappearing through the event horizon means exiting the realm of causality. Red-shifted to oblivion, in a sense.

Quote:Originally Posted by Lagboltz
Do you disagree that a constant lambda leads to an acceleration of expansion?

I disagree, for reasons already stated.

I think I have discovered why we have such a disconnect on why I don't understand your posts and you don't understand mine. The field equation of general relativity says that a constant lambda can provide the acceleration. Lambda is a constant. To explain astronomical observation lambda doesn't need to change.

Ah, but the thing is, science is also a philosophy -- complete with its own postulates and methods -- the invariance of c, conservation, etc. In fact, it is a very MATERIALIST world view. And just like any religion, its adherents could be very unforgiving to its members thought of as 'heretical'.

To me the fundamental idea of physics is to build mathematical schema that model observations. That is really more in the realm of applied mathematics, than philosophy. Strictly one might say that the philosophy of the hard sciences is that nature can always be modeled by mathematics. Philosophers have certainly delved into the ramifications of the equations, but not always successfully. For example quantum mechanics has paradoxes that puzzle the intuitive mind, but the equations themselves have no paradoxes.

 

[Lagboltz]

He replaced nothingness by an infinite regress.

Hmmmm.

Infinite regresses never bothered me. Hawking showed that time can have no beginning and end similar to the three spatial dimensions. In relativity time has the same status as space with the exception of a complex number, so Hawking's result is not surprising. In that sense nature may be playing tricks on the human mind. Intuitively it doesn't seem right that when we look at the stars, in some sense we are staring at the back of our heads if we discounted the problem of the event horizon and that our heads did not exist back then. Without knowing relativity we would think that we are staring at infinity. So time also has intuitive problems with beginnings and ends when we are thinking in terms of cosmological scales.

 

[numinus]

No, I don't mean lambda. I sent you a reference on that a while ago. Mass energy is roughly equal to the gravitational potential energy.

I'm sorry but you are not making any sense.

E=mc^2 -- mass IS energy, c^2 being the conversion factor necessary to change kilograms into newton-meter. The effect of any mass/energy on space-time is to CURVE it towards itself.

Mass energy, therefore, is contracting, NOT expanding space-time.

No. Disappearing through the event horizon means exiting the realm of causality. Red-shifted to oblivion, in a sense.

If that is what you mean, then your question becomes an essentially METAPHYSICAL question, no?

I think I have discovered why we have such a disconnect on why I don't understand your posts and you don't understand mine. The field equation of general relativity says that a constant lambda can provide the acceleration. Lambda is a constant. To explain astronomical observation lambda doesn't need to change.

Of course lambda doesn't change. It is a CONSTANT, after all.

When you multiply this constant to the metric tensor, which is expanding, you have an INCREASING repulsive tendency of space-time. Depending on the value of lambda, it would decelerate space-time contraction or accelerate space-time expansion, or derive a steady state.

But, yes, you do have a point. I was loosely refering to the negative energy of vacuum as lambda.

To me the fundamental idea of physics is to build mathematical schema that model observations. That is really more in the realm of applied mathematics, than philosophy. Strictly one might say that the philosophy of the hard sciences is that nature can always be modeled by mathematics. Philosophers have certainly delved into the ramifications of the equations, but not always successfully. For example quantum mechanics has paradoxes that puzzle the intuitive mind, but the equations themselves have no paradoxes.

I'm sorry but that is an extremely flawed way of looking at it.

http://en.wikipedia.org/wiki/Philosophy

Philosophy is the study of general problems concerning matters such as existence, knowledge, truth, beauty, justice, validity, mind, and language.[1][2] Philosophy is distinguished from other ways of addressing these questions (such as mysticism or mythology) by its critical, generally systematic approach and its reliance on reasoned argument.[3] The word philosophy is of Ancient Greek origin: φιλοσοφία (philosophía), meaning "love of wisdom."

Mathematics and the natural sciences are, themselves, philosophical inquiries.

 

[numinus]

Infinite regresses never bothered me. Hawking showed that time can have no beginning and end similar to the three spatial dimensions. In relativity time has the same status as space with the exception of a complex number, so Hawking's result is not surprising. In that sense nature may be playing tricks on the human mind. Intuitively it doesn't seem right that when we look at the stars, in some sense we are staring at the back of our heads if we discounted the problem of the event horizon and that our heads did not exist back then. Without knowing relativity we would think that we are staring at infinity. So time also has intuitive problems with beginnings and ends when we are thinking in terms of cosmological scales.

Neither am I bothered by infinity.

The point I was making is that if one suggests an infinite number of universes interacting with each other at the fringes and in ways that does not follow any logical way, then one might as well suggest god, no?

 

[Lagboltz]

Originally Posted by Lagboltz
No, I don't mean lambda. I sent you a reference on that a while ago. Mass energy is roughly equal to the gravitational potential energy.

I'm sorry but you are not making any sense.

Mass energy, therefore, is contracting, NOT expanding space-time.

There is still a disconnect. Look at the bottom of post #130 to see what I am talking about.

Of course lambda doesn't change. It is a CONSTANT, after all.

But, yes, you do have a point. I was loosely refering to the negative energy of vacuum as lambda.

That is my point, your continual reference to a changing lambda lead to a lot of confusion as to what you were thinking.

Philosophy is the study of general problems concerning matters such as existence, knowledge, truth, beauty, justice, validity, mind, and language.[1][2] Philosophy is distinguished from other ways of addressing these questions (such as mysticism or mythology) by its critical, generally systematic approach and its reliance on reasoned argument.[3] The word philosophy is of Ancient Greek origin: φιλοσοφία (philosophía), meaning "love of wisdom."

Yes I took philosophy classes too and I know what it is. However the point I was making is that physics is the only aspect of philosophy that deals rigidly with mathematical modeling.

Numinus Post # 170
The point I was making is that if one suggests an infinite number of universes interacting with each other at the fringes and in ways that does not follow any logical way, then one might as well suggest god, no?

No. The word god has many connotations. I don't know what you are referring to here. The theories behind the origin of the universe are still in the formative stages. It is sort of like the few years before special relativity when people were trying to think in terms of properties of ether, puzzling over the Michaelson-Morley experiment, and putting patches on electrodynamics.

 

[samsara15]

If there were a God, one would ask: 'who created God?'.

 

[Dr.Who]

If there were a God, one would ask: 'who created God?'.

All the laws of science tell us that the universe had to be created. We can accept that it was created or we can throw out the laws.

With god there is no such law telling us that god cannot have been existing from everlasting. We can easily propose that God was never created.

 

[Lagboltz]

In studying gravity or physics in general. All the physicist has to accept is that the universe is here, not necessarily that it was created.

The history of the center of the universe started with the flat earth, then the sun, then the milky way. Now the focus is on the big bang. Just because science does not have a successful model of the big bang doesn't mean that we have to start worrying about a more transcendental form of creation just yet. I am willing to wait a few hundred years for that to sort out. Historically the role of God has been continually pushed back as science unfolds new cosmic discoveries. Once a "theory of everything" has been formulated, then we can talk about a role for God.

 

[samsara15]

Maybe that logic works for you,. Dr Who, but it doesn't work for me. I'll go with the idea popular with most physicists that the universe has always been here, and we are still learning what may have preceded the Big Bang. Any God that may or may not exist is only the universe or the physical principles that control the universe.

 

[samsara15]

A random quantum fluctuation could have created the universe, or two branes rubbing together, or perhaps there are an infinite numbers of universes springing out of black holes...many people have many different ideas how a universe could come into being. Some even speculate we could learn how to create universes ourselves. We don't have to give up and conclude it's magic, which is what most examples of the God hypothesis do.

 

[Chip]

Existence implies eternity and suggests infinity, as nothing, the absence of all quantum particles etc., logically cannot create something.

With that in mind, it's difficult for me to buy the Big Bang as the creator of the universe, the universe, by definition, being all that there is.

After all, if we can "see" the event horizon, that only indicates that the Big Bang was quite local.

Regardless ... let's get back to gravity, as I'm enjoying reading the astute, intelligent conversation between Numinus and Lagboltz, which I find incredibly edifying, even though much of it is way beyond my technical knowledge.

 

[Dr.Who]

Maybe that logic works for you,. Dr Who, but it doesn't work for me. I'll go with the idea popular with most physicists that the universe has always been here, and we are still learning what may have preceded the Big Bang. Any God that may or may not exist is only the universe or the physical principles that control the universe.

I hate to burst you big bubble but that is not the most popular theory among physicists.

“If we accept the big bang theory, and most cosmologists now do, then a ‘creation’ of some sort is forced upon us.”

Barry Parker
Creation—the Story of the Origin and Evolution of the Universe
New York & London: Plenum Press, 1988, p. 202

If you want to make a point that a cosmologists is not a physicist then:

"Compared to the alternative of supposing that matter and energy somehow always existed, British physicist Edmund Whittaker says, “It is simpler to postulate creation ex nihilo—Divine will constituting Nature from nothingness.”

Edmund Whittaker

 

[Dr.Who]

A random quantum fluctuation could have created the universe, or two branes rubbing together, or perhaps there are an infinite numbers of universes springing out of black holes...many people have many different ideas how a universe could come into being. Some even speculate we could learn how to create universes ourselves. We don't have to give up and conclude it's magic, which is what most examples of the God hypothesis do.

The best science we have demands that one accept a supernatural beginning of the universe. The second best scientific theory we have (steady state) demands that one accept that matter is continually being created from nothing which would also be a non-materialistic or supernatural beginning.

None of that forces one to accept that the supernatural beginning is God.
Those who go on to state a God hypothesis do so because they have additional reasons.

 

[samsara15]

I have not read any cosmologists, or physicists, who accept the idea of a supernatural creation of the universe.