mooeypoo

Not if we define clocks as representing time. No, there is no difference because we define time as what represents the physical processes....... You redefine time to something that isn't acceptable by most accounts, and then you insist to make all definitions fit that.... It's an interesting philosophical endeavor, but I'm not really seeing how it's changing anything we know about anything...? Clocks don't just slow down 'cause they're tired. They slow down for a reason. We define a clock as something that represent time, and therefore when the clock slows, we say time slows. Because it's the definition, isn't it? I'm extremely confused. Even if I concede to your point that "clocks slows" doesn't equal "time slows", how is this changing anything in physics? It's language argument, isn't it?

No, it applies to our definition of time. And by your own definition of time, "event duration of physical process", time slows in high velocity. The 'event duration' is the same, always, consistently, ever, everywhere. Then, it is takes longer to a stationary observer that looks at a moving frame. INSIDE the moving frame the process takes the same. That's why time dilation depends on different frames -- in comparison. You're just refusing to use the term that's defined, but you use the same definition for it. I don't see how you're proposing anything new here, other than "don't use this particular word, use another with the same exact meaning." We can call the phenomenon "Time Hooplah", but it still shows the SAME effect. So why is it different, and why does it matter. ~mooey

No offense intended here, Appolinaria. Owl is discussing the meaning of the definition of time. Your question is about mass and carries the already not-quite-clear debate in a different direction. New threads don't cost money Just open a new one, and we can discuss that. That's what I was trying to say, you just put it much more clearly. Also, is this not how we *define* the meaning of 'time' ? By the duration something happens? There's not really any meaning to time without movement, those are interchangeable -- so the above really is the same as saying "it took longer" or "time slowed".

It's a good question, but start this in a different thread if you like, let's stick to topic on this one.

owl, isn't our definition of time "what clocks show" ? we're not talking about clocks we have at home, we are talking about atomic clocks. We define time according to them, so the clocks are not independent. I see your point, but I think you're forgetting the above point. The fact an atomic clock slows down means the internal processes of the decay are slowing down. We define time with them, and they show us time slows. What alternative explanation do you propose, other than "time slows" to describe "decay slows" ? It seems we're moving away from conceptual discussion into an argument bout definition, which is nice, but is entirely different. Not sure what you mean by that. Who treats time "as an entity"? Not relativity, really, it just uses the definition to describe what happens. What happens is that the action slows down in different frames of reference depending on speeds. We call that time, and we say 'time dilation' to describe it. I'm completely at a loss at what your point is, unless you're trying to redefine a definition just to make a point?

Nah. It's just really cold here.

Hm. Okay, here's the bottom line here: I misread your earlier comment. While I do apologize, that does not give you the right to ignore our requirement in this forum that you drop your attitude, stop being obnoxious, and start debating in a civil matter. You can be the smartest person on earth, and we would still ban you if your posts are full of mockery. We don't care who's organs are supposedly larger, Secular Sanity, we're here to do science, and our "requests" that you be civil are not really requests, they're our rules. Rules you agreed to when you checked that little box when you signed up. They're non-negotiable. If you insist on disregarding them, you won't continue to be a member here. You will be banned, regardless of whether or not you're right or wrong. Ridicule is unacceptable whether you argue with someone who made a mistake or argue with someone who actually cares to put the time and supply counter-arguments to your claims. Cheers. Consider this your final warning.

Just as long you remember, Phi, the secret knock is done with your hand. Your hand!

You say this because after years of study of QM, you found what evidence to counter his, exactly? Sorry, I'm usually not insisting on a person's level of education when claims are brought up, but in this case, it seems you are way ahead of yourself. Are you here to discuss and learn, or to shove your ideas into agreement even if they don't work? Are you ready to back up your extraordinarily extravagant claims that you know better Quantum Mechanics than Griffits and other PhD physicists (that work and handle QM in daily operation) ? I am not saying this can't be true. I'm saying the burden of proof is on you to show it is. As it is at the moment, you're just arguing (with attitude). You supplied not a shred of evidence to show you have any sort of merit to your claims. All you did is cry foul over established theory with evidence. You're the one making a claim here, and hte burden of proof is on you. Let's work with science and not bombastic arguments, okay? I'm waiting for your evidence. ~mooey

Good luck Mystery111! Hope to see you back soon.

Star dust, yes. What produced the big-ass craters on the moon? No.

Okay, a bicycle ride could do it. You have the basic kinematics, but you can also have friction/heat in the wheels (maybe have the rider stop and oil the wheels If the rider has a dynamo, you can insert electricity in there. Angular motion can be explained using the wheels movement, you can probably find a way to shove oscillations in there too. For vectors, stick a ramp or something in the middle of the track and have your rider jump it with the bike -- kinematics and vectors in one stone. What else... hmm

Gross? The picture?? Really!?

Makes you wonder how many of those asteroids would've hit the Earth if it wasn't for the moon, too..

Is this a written 'research paper' type exam? I'm not sure I understand what you mean by "about to write my physics exam" or by "going up to in 3 weeks". Also, can you give us an idea of what level of physics are we talking about? Is this highschool level? AP-physics? College? It'll give me an idea of what ideas to toss around. There are tons of "day to day" things where you can analyze the physics. How are you with sports? A swimming competition, for example, can cover kinematics (the swimmer jumps to the water, what's the best way jump, how much energy is required for what height/distance) and you have vectors (what's the best angle for the swimmer to hit the water surface, etc) fluid dynamics can account for some thermo, etc. A marathon can also be an interesting way of analyzing anything from kinematics to thermo (how much would the soles of the shoes heat up due to friction? I'm just throwing an idea) and also you can stretch it a bit to work on oscillations if the runner has some packpack or something, and is running at constant speed (bouncing up and down at certain height), measure the oscillation of some water bottle in their pack or something like that. Do any of these help? I can toss around more ideas if you want. ~mooey

So, NASA released this amazing topographical map of the far side of the moon, based on images from the Lunar Reconnaissance Orbiter (LRO): (Source: http://www.nasa.gov/mission_pages/LRO/news/lro-topo.html) But this got me thinking. On Earth we define 0-elevation as sea-level. Anything below is negative, anything above is positive. But there's no sea on the moon, or liquid water -- where's the 0-elevation defined, then? Why is this map showing negative elevation values? It just peaqued my curiosity, wasn't entirely sure. Thanks, ~mooey

Look, we respond to reports because we can't see everything. You report, we respond. More often than not, though, things happen and people don't report them, but rather go on their vigilante persuit of justice, forcing us to intervene when it's too late -- and when the entire thread requires a much stronger response. It's a LOT more difficult for us to respond against an "offending party" when the thread devolved in such a way where *many* are offending parties. It's as if you have a guy harassing you in a bar, but instead of calling the bouncer's attention to solve the issue by tossing the guy out or giving him a warning, you start a brawl. That's when the police come and guess what? They arrest everyone. You can't choose to be part of the problem and then get angry when we tell you to stop being part of the problem. For the tenth time, the issue wasn't you calling someone a hypocrite, and it wasn't about a single occurence. There are quite a number of members in this forum that are occasionally obnoxious. They don't get this type of moderation, though, and it has nothing to do with 'personally' picking on you. Some of us actually used to see your side and, perhaps, support it. You are making it EXTREMELY difficult to do that by nitpicking our claims to fit your own. You just strawmanned at least three people who made a point about the 'hypocrite' comment. Great job. The irony here, iNow, is that you don't even notice how you seem to be using the same tactics of the people you are so eagerly arguing against -- and insisting that should be ridiculed. ~mooey

Deleted the double-post.

The fact people don't find something specific funny does not mean they lack a sense of humor. I seem to have missed this point, so let me answer it now: It's not about my goals, it's about the forum's goals. I have no problem with you using whatever tool you want for your "craft", as I explicitly said multiple times in previous posts. There are other forums out there that wouldn't mind you using whatever tool you want against or for whatever person or poster you feel like. I don't argue for the destruction of those forums. They serve their purpose. The problem is that the particular forum you choose to participate in at this very moment has different goals, and as a result it *requires* different tools to wield said "craft". It has the authority to do that because you agreed to follow its rules when you signed up. You can use whatever tools you want if the place lets you use them. It seems that in a general poll of the membership, that's what the majority of the membership wants, too, and that's what the founders and staff of this forum agrees on. It's your choice whether or not to stick around, but you can't choose to stick around and actively go against the rules and then cry foul when people tell you to stop. Quite very simple, really. ~mooey

You talk as if "time dilation" is some "sci fi" concept that people simply "believe in". The fact that clocks slow down when accelerated is experimentally proven -- it shows exclusively that time passed slower to one clock (that is moving) than to another (taht isn't moving). That's what we call time dilation. I'm not quite sure what you think time dilation is, but if you think that the evidence for time dilation doesn't mean time dilation exists,you need to supply alternate explanation for that phenomenon. Accelerated clocks slow down *consistently* and correspond perfectly to the prediction (conceptually and experimentally, with math) made by relativity. What explanation do you give this phenomenon? How do you explain why the clocks repeatedly and consistently slow down?

See, this is what I meant when I said it's all about the goal. This forum's goal is education. In education, the tools are different than other places that offer general debates between like-minded people. While in other forums ridicule can be a tool to make people laugh and high-five one another (and that's perfectly acceptable), in this forum ridicule works against the point, most of the time, of offering a neutral place to offer educational insight. It's all about context. When I tutored physics, I did not treat all students alike. If a freshman, or a student who's just starting, came to me with a basic question he got stuck with because of algebra issues, I would tend to be more lenient and patient, walking him through the problem. When the same student came back, if we got stuck on the *same* issue, I could see that either he didn't understand the method we went over last time, or didn't take an effort. Since my goal was to give students the tools to handle physics on their own, I gave students the benefit of the doubt -- we would go over things again, make sure they know how to do it next time, and I'd even give them a few problems to do while I walk around to tutor other students and return to make sure the student managed to deal with the problem. When I studied with my fellow student majors, however, say, we crammed for an exam in a class we were all taking, the treatment to one another was different. We were no longer in "teaching" mode, we were in "practice" mode, and the attitude was completely different than what I'd use with students. And, of course, there are always students who used to come back again and again with the same type of question and you could see they weren't interested in *learning*, they were just there to get their homework solved by the tutors. When that happened, we reverted to other tactics, sometimes things that we would *never* use with students who are starting out their education or simply got stuck. When your goal is education, ridicule is rarely a good tool. The bottom line I'd like to emphasize in terms of my own views, is that while we're all allowed to disagree on this subject of ridicule and when and where to use it, we should all take into account, also, that this forum has rules. The staff's job is to maintain order in light of the forum's goal, and the staff views that by not allowing ridicule or attacking posts. We can argue, but we have to adhere to the rules. We can try and change those rules (like this thread seemed to begin with) -- and it might eventually succeed in some cases. But as long as the rules are there, we should adhere by them. We as staff never ban someone for ridiculing a single post, or occasionally losing their patience. We might post a moderation note to urge the discussion back to what we see as a beneficial education-oriented debate, which should just serve as a hint to the poster that thy took things too far. We're human beings, we make mistakes, and the purpose of moderation notes is to remind people to watch out of emotions getting ahead of them. It's when things get way out of hand that we're forced to make a more permanent decision, for what we see as the good of the forum, based on teh declared mission statement of this forum and its goals. Different moderators at different forums with different goals might choose different courses of action. That's part of what makes online forums unique. I think that's a fair way of going at it. ~mooey

Are you ridiculing our positive effort?

I am not sure I'd put my money on Virgin Galactic doing the 'outer space' missions or the manned ones. If I remember correctly, so far they manage to go up to about 200-300km above the surface, which is rather impressive for a manned flight, but it's not even close to being "outer space". It's about the height where the lower-level satellites are on.

Actually, it demonstrates something else, but we should really stick to the topic.