Jim Lesurf wrote:
In article ,
bcoombes
bcoombes@orangedotnet wrote:
Arny Krueger wrote:

How many dimensions are there in 3 dimensional space?
String theory currently is up to 11 dimensions.
3 dimensional space always has only 3 dimensions. The real world may
have 11 dimensions, but that's real world for you.

Sure it does Arnie, but if it is affected all the time by the other 8

"if" conditional noted. We would now need some evidence.

Writing as someone who spent decades working as an academic in Physics I
decided some years ago to not hold my breath until the theorists came up
with actual experiments whose results might show their ideas about string
theory were valid as a description of reality. So far, that was a wise
move... :-)

And will continue to be for some years I suspect.

Personally I suspect the universe requires a non-integer number of
dimensions and behaves in a fractal manner.

On that I agree with you completely (the fractal bit). I don't quite get how you
could have non-integer set of dimensions but then I've never thought that
because I don't get something would obviate it from being true.

My own guess would be pi times
e dimensions. That might end up neatly fitting the behaviour of e**(i*pi).

Does God have PI fingers and e legs, I wonder... :-)

then the whole of your friends 'we know everything about audio'
argument goes out of the window..


Sorry, but I missed where that was shown to follow.

It wasn't really there, my point was that given the total number of dimensions
and forces is definitely unknown it doesn't behove any one to make statements
like "Only four parameters are needed to define everything that matters.."
whatever follows doesn't matter

How is the original posting dependent on the universe *not* requiring 11 or 12 dimensions to
represent space/time and the observed forces, etc?


The original posting didn't have much to do with that with dimensions at all, in
response to the OP I was trying to make the point that you can't know for sure
how many parameters affect any particular kind of knowledge since we are still
*some* way from a theory of everything. After that the thread developed in an
entertaining but not particularly intelligent manner (as they do) and
dimensions cropped up. Actually I go for the Holographic theory myself, for what
that's worth.


If Mike Green showed that when he was at QMC then he didn't mention it to
me in the Senior Common Room Bar at the time. But I was never much of a
theorist. Too busy bursting crisp bags and wondering whose round it was

First things first as they say.

"bcoombes" bcoombes@orangedotnet wrote in message

The original posting didn't have much to do with that
with dimensions at all, in response to the OP I was
trying to make the point that you can't know for sure how
many parameters affect any particular kind of knowledge
since we are still *some* way from a theory of
everything.

So what do you do about the unknown parameters when you design refineries?

Do you make your refineries cost 100X extra to handle the unknown
parameters?

Do you make your drawings in 11 dimensions?

Or, is there a "Theory of everything" for refineries?

"bcoombes"


** Anencephalics like this one should have been aborted.



..... Phil

In article ,
bcoombes
bcoombes@orangedotnet wrote:
Jim Lesurf wrote:


Personally I suspect the universe requires a non-integer number of
dimensions and behaves in a fractal manner.

On that I agree with you completely (the fractal bit). I don't quite get
how you could have non-integer set of dimensions

One of those examples of the way maths can employ 'dimensions' defined in
terms of a set of properties that may not be the same as the more common
one when people think of 3D 'space'.

but then I've never thought that because I don't get something would
obviate it from being true.

....or at least useful as part of a description of reality that fits the
evidence and allows useful predictions, etc, that also turn out to fit
results,etc.

My own guess would be pi times
e dimensions. That might end up neatly fitting the behaviour of
e**(i*pi).

Does God have PI fingers and e legs, I wonder... :-)

then the whole of your friends 'we know everything about audio'
argument goes out of the window..


Sorry, but I missed where that was shown to follow.

It wasn't really there, my point was that given the total number of
dimensions and forces is definitely unknown it doesn't behove any one
to make statements like "Only four parameters are needed to define
everything that matters.." whatever follows doesn't matter

I would agree - as a personal opinion - that the statement is probably too
absolute. However to go further we then need some more parameters which can
be tested by seeing if they agree with the evidence when said evidence is
obtained in valid and assessable ways. Lacking that, the statement might be
correct.

One of the basics of science is Occam. That means not inventing or
involving other things if you have no evidential basis for them. Hence "not
knowing everything" does not mean "we know nothing", nor that we can't have
found a reliable basis for our understanding of specific areas.

And theoretical ideas can be fine for some purposes, but not for others.

So - to use your own approach of dragging other areas of Physics into this,
kicking and screaming - we can say that Newtonian mechanics is fine for
many purposes, but that we may have to resort to GR or QM in other cases.

Hence for *practical* purposes the statement you don't like may actually be
fine. To show otherwise requires evidence from suitable situations where
there were no significant method flaws. Not to simply dismiss the idea on
the basis that "we don't know everything".

As I point out, if you choose "we don't know everything" as a basis, then
essentially no ideas about reality can be accepted at all. Whereas the
reality is that what we do "know" in science actually tells us quite a lot
and is often a very accurate and reliable guide. Not perfect, but pretty
good until the next bus comes along... :-)

How is the original posting dependent on the universe *not* requiring
11 or 12 dimensions to represent space/time and the observed forces,
etc?


The original posting didn't have much to do with that with dimensions at
all, in response to the OP I was trying to make the point that you
can't know for sure how many parameters affect any particular kind of
knowledge since we are still *some* way from a theory of everything.

Nor can you know it matters - unless you have evidence to show that it
does. :-)

If Mike Green showed that when he was at QMC then he didn't mention it
to me in the Senior Common Room Bar at the time. But I was never much
of a theorist. Too busy bursting crisp bags and wondering whose round
it was

First things first as they say.

On that basis we should have made up "Crisp Theory". Hmmm... maybe that's
where he went wrong. Not strings but surfaces... 8-]

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Arny Krueger" wrote in message
...
"Brian Gaff" wrote in message
om

Well of course you are right.

Not so much.

Has anyone ever tried to
explain to someone quite why it is that in the same room
a sound of talking can some fine to the ear, but even the
best dummy head when heard through headphones placed in
the same room sounds echoed?

A well known effect.

Here's one discussion of it:

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

I've personally been part of discussions by knowledgeable audio people
discussing this no later than the early 1970s. I see that published
papers referencing the problem go back to 1953. If the acoustics of a
room are known with sufficient precision, the effect can largely be
mitigated. I first heard effective mitigation of the cocktail party effect
demonstrated in the late 1970s. In those days it took monumental amounts
of computer processing. The remaining hang-up is collecting enough data
about the acoustic environment. Not that it can't be done, but that it
takes so much leg work.

"This phenomenon is still very much a subject of research, in humans as
well as in computer implementations (where it is typically referred to as
source separation or blind source separation). The neural mechanism in
human brains is not yet fully clear."

Everybody who gets science (and I know for sure that Ethan is one of them)
knows the following mantra of science:

"All findings of science are provisional, and only relevant and accurate
until more reliable findings are obtained."

But this does not prevent Science from making some statements that may be
counter-intuitive to some, and arrogant-sounding to others. For example,
we know from Thermodynamics that machines with claimed efficiencies as low
as 30% can be effectively claiming the equivalent of perpetual motion. We
know the range of combinations of linear distortion, nonlinear distortion,
and noise that fall below the limits of human perception in a wide variety
of conditions. Other than loudspeakers, microphones, listening rooms and
performance spaces, we know how to reduce all distortions so low that
sound quality that is indistinguishable from the original can be obtained.

It obviously has to do with the brain and the ears etc,
but its still an interesting effect and the reason why
its so difficult to do live recordings that sound like you expected it
to!

One of the cardinal rules of live recording is that you have to mic much
closer than the listener's ears would be, in order to obtain a similar
balance of direct and reflected sound as the listener perceives. In a
typical room at least twice as close, and in a highly reverberant room,
its impossible even with close micing.



One of the things that has always fascinated me in this area is the human
ability to perceive 'deltas': in general, our brains are not that good at
detecting absolutes such as absolute pitch, but if you put a lump of sugar
in a cup of tea and stir it, most people will detect that change in pitch.
In a similar way - look at a landscape and it is difficult to detect recall
it all accurately, but if something moves, the eye-brain seems to pick the
change extremely quickly. So, coming back to your point above about the
cocktail party effect, the human brain does seem to have a great capability
for filtering what is necessary for survival. I suppose it could be the
caveman/ propagation of the species instinct kicking in: when faced with a
situation do I fight, flight of f**k it.

regards

Mike

Jim Lesurf wrote:
In article ,
bcoombes
bcoombes@orangedotnet wrote:
Jim Lesurf wrote:

snip

The original posting didn't have much to do with that with dimensions at
all, in response to the OP I was trying to make the point that you
can't know for sure how many parameters affect any particular kind of
knowledge since we are still *some* way from a theory of everything.

Nor can you know it matters - unless you have evidence to show that it
does. :-)


Well obviously I can't, (If I could I suspect I'd be polishing my Nobel medal
)however pre GR nobody could show that time dilation etc. mattered (or
happened) but now the GPS systems have to use relativistic effect compensation
to give accurate positions. All of which has sod all to do with designing a good
audio system in this era of course but may indicate (possibly) in the future yet
unknown effects from other dimensions could. I can't show this of course but
then neither could Newton have shown evidence for GR.


If Mike Green showed that when he was at QMC then he didn't mention it
to me in the Senior Common Room Bar at the time. But I was never much
of a theorist. Too busy bursting crisp bags and wondering whose round
it was


Speaking of which there is an interview with him in the Eureka magazine. (Free
with The Times newspaper today.)


First things first as they say.

On that basis we should have made up "Crisp Theory". Hmmm... maybe that's
where he went wrong. Not strings but surfaces... 8-]


Rings a bell somehow, some clever person is working along those lines I believe.
(Brane's anyone).

Phil Allison wrote:
"bcoombes"


** Anencephalics like this one should have been aborted.


Oh look, Phil's learnt a new long word. Now take your meds and go and have a
little lie down and you'll wake up feeling much better...of course you'll still
be a complete and utter ****wit.

In article , Signal
wrote:
MartinR wrote:

Only four parameters are needed to define everything that matters for
audio reproduction: Noise, frequency response, distortion, and
timebased errors.

"Reproduction" is only half the story.

Spoken like a parent. :-)

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Signal" wrote in message
...
MartinR wrote:

Only four parameters are needed to define everything that matters for
audio reproduction: Noise, frequency response, distortion, and
timebased errors.

"Reproduction" is only half the story.

What's the other half?

David.

"David Looser" wrote in
message
"Signal" wrote in message
...
MartinR wrote:

Only four parameters are needed to define everything
that matters for audio reproduction: Noise, frequency
response, distortion, and timebased errors.

"Reproduction" is only half the story.

What's the other half?

Recording.

But that makes Paul's comment look like complete wanking, because noise,
frequency
response, distortion, and timebase errors matter for recording as well.