A couple or three miles on the treadmill before my tea? Junk or worthwhile? If it's junk I'm having a can of beer instead
Christopher
I would expect some-one of your standing to be able to spell understand (post 151)
If humans are unable to undertand the big bang or steady state, then where did these concepts come from?
But do not worry I will not hold it against you
Saz
Excuse me. I'm the resident spelling nerd.
Tao begets one. One begets two. Two begets all things.
And I did spot skillful, but apparently that's the American spelling so I let it go.
Tao begets one. One begets two. Two begets all things.
a11 work and no play make jack a dull boy.
Lots to discuss, so I'll start with the quote about Heisenberg and Einstein. This is taken from a conversation between the two and is recounted in Heisenberg's Encounters with Einstein. The full quote runs as:
Now reading the full quote in its entirety clearly shows that the line of reasoning that Einstein was calling "nonsense" was that all theories could only contain predictions that were directly observable, something that he had previously believed. His argument was that physical theories can contain variables and quantities that are not directly observable. Hence my pointing out to you the error in your using this quote, since you had taken it out of context and "changed its meaning to suit your own ignorance." (your words, not mine!)For the first time, therefore, I now had the opportunity to talk with Einstein himself. On the way home, he questioned me about my background, my studies with Sommerfeld. But on arrival, he at once began with a central question about the philosophical foundation of the new quantum mechanics. He pointed out to me that in my mathematical description the notion of "electron path" did not occur at all, but that in a cloud chamber the track of the electron can of course be observed directly. It seemed to him absurd to claim that there was indeed an electron path in the cloud chamber, but none in the interior of the atom. The notion of a path could not be dependent, after all, on the size of the space in which the electron's movements were occuring. I defended myself to begin with by justifying in detail the necessity for abandoning the path concept within the interior of the atom. I pointed out that we cannot, in fact, observe such a path; what we actually record are frequencies of the light radiated by the atom, intensities and transition probabilities, but no actual path. And since it is but rational to introduce into a theory only such quantities as can be directly observed, the concept of electron paths ought not, in fact, to figure in the theory.
To my astonishment, Einstein was not at all satisfied with this argument. He thought that every theory in fact contains unobservable quantities. The principle of employing only observable quantities simply cannot be consistently carried out. And when I objected that in this I had merely been applying the type of philosophy that he, too, has made the basis of his special theory of relativity, he answered simply: "Perhaps I did use such philosophy earlier, and also wrote of it, but it is nonsense all the same."... ...He pointed out to me that the very concept of observation was itself already problematic. Every observation, so he argued, presupposes that there is an unambiguous connection known to us, between the phenomenon to be observed and the sensation which eventually penetrates into our consciousness. But we can only be sure of this connection, if we know the natural laws by which it is determined. If, however, as is obviously the case in modern atomic physics, these laws have to be called into question, then even the concept of "observation" loses its clear meaning. In that case, it is the theory which first determines what can be observed.
Can you please let me know the exact quote where Hawking states the Universe was created out of "absolutely nothing," I cannot find the exact location of him saying this.
However, it should be pointed out to that the theory of the big bang came about due to a prediction that came from General Relativity, that suggested that the Universe was expanding. Einstein didn't like this and introduced a cosmological constant to produce a steady state Universe. Later, when Edwin Hubble directly measured the expansion of the Universe using galactic redshift, Einstein called the introduction of the cosmological constant "my greatest mistake." However more recent measurements and observations have shown that the expansion of the universe is actually increasing and so that Einstein was right in postulating his Cosmological constant. Thus, the idea Universe being created out of "absolutely nothing" comes from the theory, rather than the theory being dependant on it. Even then, this is not the actually what the theory says - it states that the beginning of the Universe was a singularity - a point where our current mathematical and physical knowledge breaks down. A more accurate way to describe the big bang was an infinitesimally small point containing an infinite amount of energy. This difficult concept is often broken down by the media (not the science media though) and lay people into "coming from absolutely nothing."
There are people who understand both of the theories of General Relativity (actually reasonably easy to get your head round given some time) and Quantum Mechanics (very, very difficult to get your head around some of the more difficult concepts), although I will admit that those who do fully understand Quantum theory are a relatively select bunch. I don't understand it properly (I'm ok on the basics, but when it gets to QED, it gets difficult), so don't feel bad that you don't either. I would guess that less than a thousand people in the world fully understand the theory.
Using your rabbit out of the hat analogy: when a physicist shows the Universe and its properties and the proceeds to describe it using a Physical theory, the theory didn't come out of 'absolutely nothing.' Even an eight year old child understands that.