michel123456

I was wondering on your comment. An then I made the following thought: why is the fourth coordinate called "time"? If the fourth coordinate was a spatial one, what would be the difference? The truck at coordinates W,x,y,z will crash you if you are at the same W,x,y,z coordinates, but if you are at a different spatial coordinate W2,x,y,z, the truck will not crash upon you (I put intentionaly W instead of T). Then I thought the only difference between x,y,z and W would be the arrow of time: W coordinates are always changing, always growing, in such a way that you cannot go back twice to the same coordinates. But that does not make this fourth coordinate "unreal". It makes the W coordinate more real than anything else: it represents something that is happening very deep in our essence as material objects. So I agree with Swansont. On this point. BUT if "time is slowing" in some circumstances, one could tell what is the regular speed of time ?

Exactly. I agree 100%

But the black line has a very peculiar property: since no interaction can happen in zero time, no interaction can happen between the elements of the black line. The black line is a "dead body", meaning that there can be no direct bindings beween its elements.

I guess the question is: _are you in a house? _are you a box? Then the answer is I am in a house.

To clarify, what is your understanding of "the present is the only time ever happening". Where is "what is happening" in the following diagram? Is it in the black zone (in the present) or the blue (in the past)?

Too many definitions of time are circular. Not good. "A to B" is a bit sybillic, but not so bad. "To B" or not "to B", that's the question. Sorry I couldn't resist.

But you must know that true present is not observable. What we believe is present is in fact the past. _____________ I can't resist to have a look back at my beautiful pencil universe.

Related to astronauts & technology, there is another remark to observe: As much technology evolves, as much we build we lights & lighter elements*, not with bigger elements. For example, we begin with megalithic structures, then pyramids with huge blocks, then Greek temples with smaller blocks, then Roman bridges with bricks. Then Spanish fortresses with plate bricks, then construction with sand & gravel (concrete). Today construction with plaster board. I suppose it is the consequence of labor cost. When you have slaves, labor costs almost nothing in relation to the cost of raw material. Today, material must be studied in order to reduce labor cost as possible. It seems to go in parallel with the increase of human wealth. *I should have stated: elements easy to put in place. --------------------- IOW the use of extremely large elements is not the footprint of a developped technology. Our developped technology is much more about microchips than a huge stone somewhere in a park, that interest only a few artists.

My position is that we have a false interpretation of the findings. First of all, the development of techniques has nothing to do with intelligence. Ancient people were not dumb, then getting smarter and smarter until now. Some arborigen in some desert may be more intelligent than a surgeon in Washington D.C., other thing is knowledge, other thing is intelligence. Maybe Neanderthal was smarter than us, we simply don't know. The same goes for ancient civilisations: we don't know how smart they were. Most probably they were simply as smart as we are today. Secondly, human constructions do not resist well through time. Not because they are not well done, but because humans tend to destroy systematically what has been constructed by others. Most churches are constructed upon ancient basement of paganic temples, sometimes neolithic sites. The same goes for fortresses, castles, cities, etc. As a result, most very ancient remains are in nowadays deserts. Not because ancient people liked to build in deserts, but because recent civilisations avoid to build (and destroy) in such inhospitable places. So when someone discovers a wonderful site like Gobekli Tepe, he first should wonder how is it possible to have survived human destruction. Because if Gobekli Tepe was possible, there should be many Gobeklies examples over the world. The answer is that for some unknown reason the site was intentionaly covered. That is the reason why Gobekli survived. Most probably, other Gobeklies were destroyed and their stones used in some other works, as it is a very common way to find cheap construction material still today. It is exactly as if you found a bone of some paleolithic human specie: that would not mean that it is the only single bone that existed in the paleolithic, that would mean that it is the only bone that survived. If you were to find a hundred Gobeklies, maybe we would have another conception of what were the capabilities of those smart ancient people.

I disagree with the OP It is based on the false intuition that distance, the simplest feature of space, is free of time. It is not. Distance cannot exist whithout time. If distance could exist as a pure timeless entity, then any relation "at a distance" could occur whithout time, and we know that it is not physically allowed. You cannot draw a circle on a sheet of paper whithout time. The internal geometrical relations of a circle, like Pi R^2, contain time, although intuition tells us otherwise. To me, Time is not only linked to distance & space. Time is fundamentally linked to gravity. Time is so fundamental that nothing can exist without it. Or to say it otherwise, physical existence is the fundamental source of time. IMHO of course.

IIRC there is only one dimension of time in M-Theory, all the others are spatial ones.

I suppose the heting system is not supposed to be used to whole year round. What are the weather conditions in the area? In my mediterranean country, exterior spaces are sometimes heated by radiation (simple or impressive like this one) but only in several urban places where there is no substantial room inside. In resort hotels that are closed during the winter, no heating system exist in exterior areas at all, because during low season there are also less tourists and they all fill inside. You must first take a serious look at the probability of occupation of your exterior area before engaging into high cost installation. As for the deck, you must know that wood is an excellent insulator, and a very bad radiant. It is not a good material to use with floor heating. If you really want to use wood, I would suggest to find another heating solution. If you are sure the heating system is most adequate, you could replace wood with ceramics. There are excellent tiles that mimic wood, dimension about 15 cm wide & 90 cm long, from many providers.

You seem to agree that gravity exists. You also stated that gravity is related to time. I guess you understand that gravity is related to distance too. And that distance is related to time , because a distance cannot be traveled by anything in no time. IMHO the fact that we don't understand the nature of time is not a sufficient reason to negate its existence completely. Something that does not exist cannot be an element of comprehension of gravity and distance.

In our times the one who emits gas is to blame. _________________ IMHO the best way to prove time travel is not to bring information from the future because we cannot go there to double-check the info. The best way is to prove that you can go further back in time by posting tomorrow something on this forum in 2003 for example.

I don't get it, is that 60 cm above the concrete slab? with open joints?

Bring me cassoulet from Castelnaudary, and saucisses de Toulouse, with foie gras. My best memories are from there, a long time ago... And there a lot of instructive things to learn: about the way a lock work, the way the canal was build, the peculiar engraving on the stones, etc. Simply a dream. Here below the canal over the river at Bezier, build circa 1680

Is it for use under a wooden deck? Exterior? If yes it is not exactly adequate IMHO.

The Daedalus airplane has pedals. Maybe you can find more information about it. Canal du Midi, wonderful ! ----------------------------- about pedal power. Note that the seat is up, like on a bicycle, and not down like in your link.

That is a good basis for discussion. Physically speaking, electricity is the most uneffective way for heating. Generally, electricity is produced from fuel or gas that heats water, producing vapor in a turbine with IIRC more than 50% energetic loss, then transmit through wires (other loss), then retransformed in heat (another loss). The whole process is dumb: why not use gas or fuel directly to produce heat where you need it. So under this POV Captain is right. Things change when electricity production does not depend on fossil fuels but on renewable energy, wind or solar. In this case you care much less about energy losses and electric heating becomes green. If electricity comes fron nuclear source, the question whether it is green or not is still open. All this not regarding the cost. This article about efficiency.

Note that acceleration is only the second derivative of motion. Less known is jerk, the third derivative, and jounce the fourth. I guess there is no end to this. This a fun article FYI.

We have seen that before.

You were serious. I need a beer now. Is there a mod here around to split this thread into "do you believe unicorns once existed?" We've gone far from Analysis & Calculus.

Did a touch something taboo?

Aouch. You cannot be serious.

Phi, there is a hidden agenda.