studiot

I would advise anyone wanting to look more deeply into the extinction/evolutionary aspects of this to read Benton's excellent book. Benton is professor of paleogeology at Bristol University, and heavily involved in the reasearch. So the book is written for the semi knowledgeable layman but is rock solid in content and references . It treats all 5 known major extinction events as well as some background material.

Yes indeed, strictly so. Also since the centrifugal force is imaginary, we really should instigate a more complicated analysis. However the effect still affects the direction of gravity since the rotation causing this apparent reduction in the magnitude of gravity is not in the plane of the gravitational attraction, so the effect depends upon latitude and the forces necessary to calculate the normal force must be added vectorially.

You have to be very careful with negating a compound proposition or statement. For example the negation of "love is blind" could be "something other than love is blind" eg "A worm is blind" . In this case not p is true.

I'm sorry but I honestly think that article really is word salad , perhaps linked to budget seeking.

I like this +1 Maybe so, but introducing emergent adds another ill defined concept. Which leads to others using a different definition of the word in response. We had a long but inconclusive discussion about the meaning of emergent before either of your times here.

Hello Jamss, and welcome. The equations need to be worked as ratios in the problem since you don't know the actual values of the masses. You obtain this from the ratio of two applications of the equation: heat input = mass times specific heat times temperature rise = constant power times time. This ratio can then be used in similar equations to find the latent heat ratio.

Genady is correct the density and distribution of the mass makes a difference. There is nothing wrong with your maths, but note you initial conditions. However there is more to this than meets the eye since gravity, whether considered as force or as an acceleration is a vector, not a scalar. The distribition and density of the mass affects the direction of gravity. So the geometric centre and the centr of gravity no longer conincide. It is interesting to note the the discovery of the massiveness of the Himalaya was discovered by Everest from deductions on observations variations of alignment of plumb bobs on the plains beneath. Yet another effect has not been mentioned and is oft forgot. The reason why gravity is greater at the poles than the equator , due to centrigugal effects of our spinning planet. Once again this also has an effect on direction.

Your patience is exemplary. +1

I agree with Genady and Ghideon. In fact if you read the text very carefully the text refers to skate A and Skater B. The walls are referred to in the plural and not distinguished. However you are correct in realising that the mass of the walls is irrelevant. So take heart this was a very poorly drafted question. I would be interested to learn where it came from please ?

Very interesting to get the up to date facts. +1 I haven't done any of this stuff since the late 1970s/early 1980s My textbook then was Laurila.

There are quite a few more popular threads with over 1000 responses. These tend to be less technical. To be precise the theory of algebraic varieties. Although strangely enough this has a great deal to do with geometry. The most interesting thing about the geometry of n dimensions is that it has few applications except in the realm of statistics where it is considered vital knowledge for higher level study. Indeed it is the aspects of Time that are non geometric that set it apart from the other variables in GR. What did you make of my recent comments about the connections between time and movement ?

Glad to be of assistance. Re-reading my last post I see my spellung wasn't perfect either ! If you need any references for example for the photogrammetry I can easily supply some.

Yes, but I didn't make the claim about 'flatness', you did. So it is up to you to support it properly. Note I have added some useful equations to my last post. It should also be noted that GR does not embody or use all aspects of the Nature of Time (the topic of this thread), although I think we are all agreed that a 'timelike' variable incorporating some of these are necessary for GR. So discussion should not be limited to GR

That is not mathematical. Curvature in 1 dimension had no parameters and does not exist. Curvature in 2 dimensions involves one parameter usually called kappa, and refers to lines. Curvature in 3 dimensions involves two parameters usually called kappa and tau and refers to surfaces. When we move to 4 dimensions this involves abother parameter, usually called sigma and involves blocks of 3D space. Mathematically I would expect to see a discussion of this., in terms of the Gaussian or Riemanian curvature matrices. The parameters correspond to directions and expanded they correspond to 4 scalar equations [math]\frac{{dT}}{{ds}} = \kappa N[/math] [math]\frac{{dT}}{{ds}} = - \kappa N + \tau B[/math] [math]\frac{{dB}}{{ds}} = - \tau N + \sigma D[/math] [math]\frac{{dD}}{{ds}} = - \sigma B[/math]

Again I must emphasise something Markus said. But it is even more complicated than this. To fully appreciate the depth of this statement - in relation to the nature of time - we need to bring together several disciplines. In doing so we need to avoid the trap of introducing extraneous concepts and matters from these several disciplines that are associated with material we need. I suggest the disciplines are at least and in no particular order:- language (semantics), general philosophy, physics, pure mathematics, applied mathematics. We need to consider carefully the meaning of at least the terms, again in no particular order:- movement, virtual, geometry, space and dimension, embedded. As a matter of interest an example of movement that occurs without time in physics is called a virtual displacement. Further examples occur in mathematics, particularly in geometry. You cannot fully consider congruence, similarity and transformations without some sort of movement-without-time. Finally a warning about mathematics. Nearly all courses and texts on 'the geometry of n dimensions' assume an underlying embedding in n+1 dimensions. Furthermore most such geometries are static. That is they are without movement. It is physics that introduces the movement in it's efforts to model the 'real' world around us. This is an absolutely huge subject. I would like to see the mathematics supporting this statement.

I have no idea what this is all about. And I still don't see a 'big problem'. Surely we need to answer more fundamental ones before we can arrive at a definition of consciousness ? For example is life necessary for consciousness ?, Which of course begs the question "What is life ?"

As far as I know 'follow' comes up automatically ie the box is ticked when I start a thread. Perhaps someone with more knowledge of the system might advise you on this.

Thanks. How did you get on with the acoustics material I posted ?

Very interesting viewpoint. +1 So as I understand you you are saying you can't have the future together with the past because they are using the same energy ?? Also interesting, and brings out the point I have been making repeatedly that space and time are different. +1 One of the difference is that when we draw a graph or plot we are using the properties of space exclusively. We generate virtual surfaces and other complicated shapes in the space we draw in but thay are all spatial. The mathematical geometry of n dimensions is based on this fact eg Kendall 1961. I am still thinking about the situation when we convert them to all timelike.

Interesting use of projective geometry. Towards the beginning of your video you spell distortion as distorsion. I see you are Spanish so no bother I mis-spell words all the time but hey you might like to correct this. I have a friend who is an artist and a draftsman. Very non scientifically technical, non computerate. Yet although I can calculate the effect on shapes, and he cannot, I cannot anywhere near match the way he has taken to drawing programs and can produce the most amazing pictures intuitively and takes equally intuitively to the use of the computer to automatically perform the calculations for him. Which brings me to my point that although you have really used your time well, you have not discovered anything new. Sorry. Mathematicians call your infinity point : "the point at infinity" so a good match. This is a branch of projective geometry which was developed in the 19th century. This is not taught much today, but of great use in compter graphics. It is also of great use in cartography, where it is used to take out the distortion that arises in aerial photography and also to provide information in the 3rd Dimension (Height in this case). This branch of cartography is called photogrammetry. Hope this helps and go well. +1 By the way, phi, I liked the embedding of the video as it plays on SF, but my older computer no longer renders YT etc.

And just who are you to use abnormal definitions of scientific terms. The term massive refers to those bodies which possess the property of mass and distinguishes it from those that do not.

http://gamelab.mit.edu/games/a-slower-speed-of-light/ Have fun folks

So what's the big problem ?

Can you elaborate on this without employing a circular argument ?

Indeed +1 Agreed. +1 is meant to be about or why it is off topic to talk about some aspects of that nature and not others. I still don't know what an opening post that looks more like a blog entitled the nature of time The whole point being that space and time are very different things. I note that at one point responders generally agree that time is not a 'thing', yet returned to treat it as a 'thing' - after all if it it not a thing how can it have properties? "Time is a dimension" So do we take addison's proposal as an invitation to discuss or what ?