« Last post by Ethos_ on Today at 21:57:24 »
It appears science has no conclusive evidence yet as to whether the universe is finite or infinite. The following link explains:
« Last post by yor_on on Today at 21:45:41 »
Hmm, think you're a little hard on us there Pete. It's not only John that gets confused thinking of gravity as negative energy. I saw someone arguing that Stephen Hawking defined it this way. "Two pieces of matter that are close to each other have less [positive] energy than the same two pieces a long way apart, because you have to expend energy to separate them against the gravitational force that is pulling them together,"
But if we look at frame dependencies imagining a far away 'inertial' observer, observing the gravitational acceleration of a black box, from his frame finding the the box to gain energy as it falls to earth. So, how does it gain a constantly building, positive energy, from this negative?
And for the observer inside that black box, there is no 'new energy' to be measured as I know of. And from his frame it's Earth coming to get him, as he have no way to define a motion.
could be that there is a simpler definition of it than Hawking's, but reading his argument I get confused too. Also, inside that black box there shouldn't be a thing differing his 'free fall' from any other uniform motion, that as far as I can see, no matter if our inertial observer defines it as accelerating. Is there no other way to define it than using gravity as negative energy to get to a equilibrium?
(all of it ideally, ignoring spin.)
« Last post by dlorde on Today at 21:28:15 »
The whole universe is quantum mechanical in fact , as you know .
So accept what quantum field theory tells you. No unknown fields or forces that can influence your brain. No psi, or paranormal, or supernatural influences. Welcome to the real world.
« Last post by dlorde on Today at 21:13:54 »
Many eminent physicists talk about the conscious collapse of the wave function : see Carter's excerpts .
It's an interpretation of what the means in physical terms; a wavefunction in superposition of states appears to collapse to a single state under interaction/measurement/observation. You can intepret this as a real wavefunction collapse or as one observer's view of a bigger picture where the wavefunction continues to evolve in superposition, but encompasses the observer in that superposition. The former has multiple difficulties explaining what 'wavefunction collapse' really means and precisely when it occurs, the latter says there really isn't a collapse, but has a large incredulity factor (because it involves the concept of a multiverse).
What kindda scientific mess or confusion is this then ? Science sounds like some sort of a religion regarding the interpretation of quantum theory at least : so many scientific "sectes " lol telling different stories about the same theory and more
The theory is fine, it's the best theory ever devised, and works like a charm. The interpretations are ways to get you head around what's actually happening. Many physicists say 'forget the interpretations, just shut up and calculate'.
... how can Caroll say with such unscientific confidence that the standard model of quantum field theory rules out the existence of any psi phenomena ...? since the materialist theory of the nature of reality is certainly false .
He explains it in painstaking detail in the lecture. QFT does such a good job of predicting how the world behaves at levels and energies including, and way beyond, the everyday, and its predictions have been so thoroughly tested at everyday levels (and beyond) that it's beyond all reasonable doubt that its model of the everyday is correct; plus, if there were any novel interactions strong enough to be relevant to our everyday world, they would have been detected by tests sensitive enough to detect interactions way below the threshold of everyday molecular biology interactions. Either something interacts or it doesn't. If it does, you can see the results of the interaction; if it doesn't, it isn't relevant.
« Last post by dlorde on Today at 20:55:16 »
I too can't see how something can come from 'true' nothing (i.e. absence of anything, including spacetime). On the other hand, if the universe is closed in time (time has a beginning), what does it mean to say there's always been something...
« Last post by mriver8 on Today at 20:07:32 »
« Last post by mriver8 on Today at 19:47:51 »
If you know the frequency of the alien ultrasound (use a bat detector to scan it) you can make "ultrasound chaff" with a car reversing transducer and baffle the buggers.
« Last post by demografx on Today at 19:09:38 »
Uhhhhh.....considering the context here.......please clarify that sound.
« Last post by demografx on Today at 18:55:32 »
Physiology & Medicine / Re: What foods can stop cataracts, and is there a conspiracy to stop us finding out?« Last post by Bored chemist on Today at 18:07:57 »
Why do you think food has anything to do with cataracts?
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