the world is like a goldfish bowl

[Sanford]

Prof. Hawking said the world is like a goldfish bowl. Just as the fish knows only the bowl, we only know what we see. Hawking simply does not understand what science is, for him to make such a statement!

 

A science theory is based upon mathematics, which is a collection of arbitrary fully consistent statements. The theory must also agree somewhat with observations and experiments. The fish does not understand mathematics, as mathematics is a human creation, and so the fish does not have a scientific understanding of the world.

 

General Relativity is a valid theory, as the mathematics is consistent, and many observations (not all) agree with the theory. Quantum mechanics is also a valid theory. However, these conflict, as the mathematical assumptions are different. We can live with this conflict, as relativity deals with large objects like planets, and quantum mechanics deals with small objects like atoms. Currently, it is impossible to measure the gravitational force between two atoms, and so we cannot make an experiment to determine which theory is correct.

 

Hawking speaks a lot about the nature of the universe. Here he is out of his league. There is currently no theory of cosmology, that is, there is no consistent mathematical framework that agrees with observations. The reason is that current theories, general relativity and quantum mechanics conflict with each other, and both are needed for a correct explanation of cosmology. All discussions of cosmology, such as the Big Bang idea, are hypotheses, that is, guesses, not rigorous scientific theories. We must be careful not to confuse theories, which are rigorous explanations, with hypotheses, which are guesses hopefully paving the way to a theory.

[IM Egdall]

Unfortunately, physicists use the same word "theory" for something that has loads of supporting empirical evidence, as well as for something that has virtually none (like quantum theory and string theory, respectively). But I take umbrage with your referring to the Big Bang as just a hypothesis or idea. It is a theory substantiated by an impressive set of independent observations. To quote from a book I am writing on relativity for the lay person:

"Today the big bang theory is widely accepted by physicists as the best current explanation for the geometry, composition, and history of the universe. Why? Because a number of measurements from vastly different observations agree with modern big bang theory predictions (to a precision of 10% or better). This is a most remarkable agreement, considering the measurement challenges and the fact that we are talking about something that began some 13.66 billion years ago. Current evidence for the big bang includes:

 

1) the homogeneity of the universe

 

2) the expansion of the universe

 

3) the amount and abundance of helium and other light elements in our universe

 

4) the Cosmic Microwave Background and the fluctuations in the CMB

 

5) the large scale structure of the universe

 

6) the age of stars

 

7) the evolution of galaxies, and

 

8) a number of other more esoteric measurements.

 

(<BR clear=all> B. Feuerbacher and R. Scranton, "Evidence for the Big Bang", The TalkOrigins Archive, Jan. 2006. http://www.talkorigi...#smallstructure

 

 

Edited September 13, 2010 by I ME

[tomgwyther]

Prof. Hawking said "The world is like a goldfish bowl. Just as the fish knows only the bowl, we only know what we see"

 

The context of this statement is this:

"Hawking also touched on the need for some cosmic perspective, too.

He compared humanity's view of the universe to that of a goldfish looking out of its bowl, saying that we can't be sure our view is the "correct" one. We might be in a giant goldfish bowl, for there is no single, absolute picture of reality, he added."

 

"A science theory is based upon mathematics, which is a collection of arbitrary fully consistent statements. The theory must also agree somewhat with observations and experiments."

 

Not entirely true. A theory is based on observations (Theory from the Latin, Theoria, meaning 'It has been observed')

Moreover, theory must agree with observations. Mathematics is used to describe theory and make predictions. Also, whether or not the fish understands mathematics isn't the point of the quotation.

 

"Hawking speaks a lot about the nature of the universe. Here he is out of his league. There is currently no theory of cosmology,"

Which is exactly the point his 'gold fish' analogy is trying to make.

[michel123456]

Theoria (Greek θεωρία) is Greek for contemplation.

[tomgwyther]

My bad Michel... got my Greek and Latin mixed up. here's a better definition for Sanford from Wiki.

 

In philosophy, theory (from ancient Greek theoria, θεωρία, meaning "a looking at, viewing, beholding") refers to contemplation or speculation,

 

My Greek speaking is limited rude words and ordering fast food!

Edited September 16, 2010 by tomgwyther