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Dinosaurs could certainly live in many areas of the earth today. Birds are direct descendants of feathered dinosaurs, so birds are actually the only remaining dinosaurs.

Very sad news, a legend of film, and the pride of Scotland, has passed. The orginal ( and best ) James Bond, Captain Remus. Jimmy Malone and John Mason, has passed after a distinguished career. Remembering Swansont's previous avatar, I offer my condolences.

For thought experiments you can break some, and maintain others, even sometimes without running into a logical contradiction. Not that reality would agree with the conclusions...

Science is by definition, repeatable. Emotional responses don't allow for that. But I agree that the term 'scientist' is nebulous at best. Another example … Is someone who tries to expand our knowledge, either through experiment or theory, using the scientific method, but doesn't actually accomplish anything a 'scientist ' ? ( see A Einstein in his later years, working on a unified field theory; would anyone say he wasn't a scientist ? )

Neither. You moved (impossibly) on the "grid", but as described you simply did it all in the same frame . Points A, C, and B are all in the same frame and you moved spatially only in that frame. You would have travelled forward or backward in time in some other frames, but not in that one. So you travelled in time relative to neither star.

Supposing that those areas remain stable as it is now. But I am not sure this is the case... Some people think that we are going through a mass-extinction phase right now, caused by rapidly changing environment due to human activity. In any case, it might be that at the moment the environment is changing too fast on the global scope that very large animals could thrive. My understanding is that large animals have difficulties in rapidly changing environments because they are generally slow to reproduce (and thus adapt by evolutionary change). Humans might be an exception because we have a technology that we can adapt instead of our own bodies.

Here's part of a post someone metaresearched on the composition on a vinyl record forum. Might give a clue to the chemists here.... More here: https://www.vinylengine.com/turntable_forum/viewtopic.php?t=99579

Even without much time (or energy) to think, it sounds about right to me. And the reason is that you're going to a point outside the light cone of both departure points. That is known technically as "outside the causal cone." The future light cone of event "departure from A" is seen as the future of "departure from A" by all inertial observers. Analogously respect to the past. But areas outside, like the point event you're proposing, are neither past nor future. Some inertial observers will see them as future of either A or B; others will see it as past.

When you arrive at point C, you will see the same light coming from both stars as someone who never moved from point C; Light that left both stars 5 yrs ago. You see both stars as they were 5 yrs ago.

Yes, no and it depends. Problem is that when instant travel or instant exchange of information is introduced into accepted theories of relativity the theories does not predict what is supposed to happen. I think the thought experiment is interesting as a way to see how and why problems arise. As far as I can tell: Lets remove the magic from the post it and assume that A, B and C are not moving relative to one another. Then your description seems to match what observers, stationary at A, B and C, would be calculating using mainstream theories. Observations from C, using a telescope to look at a synchronised clocks located at the other locations (A and B) seems to fit your description.

I think your larger just before a mass extinction effect is a bit of an illusion but there are some real world reasons this appears to be true even though currently I would say that mammals had their heyday around 2 million or more years ago and currently land animals are bit smaller on average than during Pliocene but Dinosaurs are or were "pre evolved" to be larger, this can be seen from modern living dinosaurs who have hollow bones and more advanced circulatory and lung systems compared to mammals. The largest mammal that ever lived was related to rhinoceros's and was as large as many dinosaurs. Mammals are burdened by heavier but less strong skeletons, less advanced breathing/circulatory systems, and a reproductive system that puts larger adults in a precarious place the larger they get.

Yesterday, it was too late. OK. Now, I made program in C/C++: #include <stdio.h> //int primes[] = { 2, 3, 5, -1 }; int primes[] = { 2, 3, 5, 7, 11, 13, 17, 19, 23, -1 }; bool check(int a, int b) { for (int i = 0; primes[i] > 0; i++) { if ((a % primes[i]) == 0) return(false); if ((b % primes[i]) == 0) return(false); } return(true); } int main(int argc, int *argv[]) { int count = 0; int end = 1; printf("Primes: "); for (int i = 0; primes[i] > 0; i++) { printf("%d ", primes[i]); end *= primes[i]; } printf("\n"); printf("End %d\n", end); int half = end / 2; for (int i = 0; i < half; i++) { int a = i; int b = end - a; if (check(a, b)) { //printf("Found %d %d\n", a, b); count++; } } printf("Count %d\n", count); return(0); } For test case with 3 primes it gave: Which looks good. For OP problem with 9 primes it gave too many results to show them all (so had to disable printf()): 18 mln is over twice more than OP value.

i probably phrased my question badly. I was not suggesting that the large animals were the cause of the extinction. but rather, i was suggesting that it is a natural for animals to continue to grow larger and larger unless inhibited by mass extinction events , whatever the cause

With any luck, pending legal proceedings will knock that one on the head.

Yes, but in that case there might be a prefix missing somewhere in the definition. 😃

The point is that prime no prime number greater than 23 is divisible by any of the first 9 primes. So each prime number and its pair which adds to make 223092870 will be candidates for inclusion and so must be checked. and there are a great many prime numbers up to 9 digits long. But added to these are numbers which are not prime yet still not divisible by any of the first 9 primes such as the example 2419 I gave. All of these must also be checked.

Now that I think about it, the product of the first 23 is, as you say, 223092870. Now, the number of ways in which you can sum two (arbitrary) natural numbers to give N is just 111'546'435, because 223'092'870 is even. So the problem reduces to finding how many numbers there are between 1 and 111'546'435 that are not divided by 1, 2, 3, 5, ..., 23 (the 1st 23 primes). The only thing I can say is that's not an elementary problem. How did you get your conjecture @Tinacity? Counterexample: \( \pi \) is irrational; \( 1-\pi \) is irrational too. but \( \pi + 1- \pi = 1 \).

! Moderator Note That's not how discussion works. It sounds like you're just "winging it" each time, and spouting out whatever pops into your mind. It's a style much more suited to blogging (or not writing at all, but instead focusing on reading). It's against the rules in a discussion here. I'm sorry, but our Speculations section requires you to support your arguments with mainstream evidence and observations. It doesn't look like you're prepared to do that, and doesn't everyone have better things to do? Thread closed. Please don't post WAG explanations like that here anymore.

Why the fixation? Large is just a number...