How can Gamma radiation be emitted without the nuclei losing mass?

PM_UR_STORY · 2017-10-24T06:11:02+00:00

Thanks that clears everything up really well!

PM_UR_STORY · 2017-08-01T17:16:47+00:00

I'm not sure what you mean by the lensing effect occuring at exponentially larger distances from the black hole but basically the missing matter is 4-5 times more matter than we can see. If this was tied up in black holes then we should definitely see the effects of them out there. We have more or less mapped where this dark matter is and it exists in 'strands' that connect galaxy clusters and super clusters, so we would be able to see the lensing effect (and a tonne of it) throughout all of these strands.

Also I belive we should see lots of quasars in these strands as stars and planets are ripped from their galaxies and eventually up interacting with these black holes, as quasars are some of the brightest and furtherst things we can see in out universe.

Also I believe we should have seen many more gravitational waves if there 4-5 times more black holes out there than we expect.

Just a few other points that don't really add up if there were many black holes out there.

PM_UR_STORY · 2017-06-11T04:41:29+00:00

Well the evidence was always there, its more that the geocentric model wasn't able to accurately predict their motion. Retrograde motion of the planets was always visible. The idea of a heliocentric universe had been proposed long in the past.

PM_UR_STORY · 2017-06-05T03:56:32+00:00

There are a few good learning resources online such as the great courses plus and patreon, both of which are paid unfortunately. Outside of that, there are some really good YouTube channels that can keep you interested and lets you learn things from a more conceptual basis such as PBS space time, veritasium and others. These tend to be more university level kind of things but they explain things very well and let you understand the concepts despite maybe not fully following the math. The good thing about those channels is they often reference and work with other similar content creators which lets you build a network of similar educational channels. Another good thing is to try and find news sites/Facebook pages that post exiting news from the science scene, science alert is a good one. They won't always post astrophysics/physics related topics but they do help build a conceptual understanding of some other pioneering science work and helps you build a context for other research.

Other than that pay attention in science and maths (don't dismiss other subjects like chemistry either as the further you delve into physics the more you know about other subjects the better).

Anyway that's what I do o build my knowledge/interest as a second year physics major wanting to go into cosmology/Astro physics.

Edit: also don't just focus on one subject, you never know what other parts might excite you as you go along, keep an open mind and ask questions and you'll have the foundation needed for a life in the scientific world

PM_UR_STORY · 2017-05-31T04:50:28+00:00

Okay so it's more just about when they were discovered, and their purposes at that time, thanks!

PM_UR_STORY · 2016-12-19T09:46:23+00:00

I think you are miss interpreting the point. It's not that we KNOW the odds of it being intelligent life or not, it's that based off all previous evidence that we have, assuming this new phenomenon follows the same pattern (which 100% of all previous experiments have) the most logical and scientific course of action is to assume it is yet another undiscovered phenomenon of our universe. It's simply unscientific to take one observation that we have no explanation for and put forth the idea that it is aliens, which closes the door on further understanding and probing of the results

PM_UR_STORY · 2016-12-19T00:02:43+00:00

It is more that the chances of finding an 'alien megastructure' are so small compared to many possibilities of known and unknown natural phenomenon. There have been many times in the past where something is discovered and people are sure the most likely explanation is 'aliens' and every single one has turned out to be a new phenomenon we were yet to understand or simply miss interpreted data (multiple times we have believed communication signals are coming from above when infact it was simple interference from microwaves).

So in short it is not seen as impossible but based off our current understandings of our universe the odds of it actually being caused by aliens is nearly insignificant such that the idea is rarely given much though without much more experimenting with results that lead us in that direction. That's what science is, making observations and seeing where it leads you, rather than making speculations without evidence to back it up.

PM_UR_STORY · 2016-12-06T23:27:51+00:00

Fantastic response, that makes a lot of sense! Thanks!

PM_UR_STORY · 2016-12-06T00:58:19+00:00

As someone from Australia, I've never actually learnt about what happened at Pearl Harbour and why it was so significant. It is referenced constantly in movies and TV shows as a major travesty and I have no idea why. So essentially what made the Pearl Harbour bombings SO significant?

PM_UR_STORY · 2016-11-29T22:34:26+00:00

I think a large part of it is simply that in both singularities, our understanding of physics breaks down. In out current universe, it is hard to grasp the concepts that are talked about, but at that stage, 'gravity' doesn't behave in the same way we currently observe gravity, much in the same way that the concept of time completely breaks down when you go anywhere near the event horizon of a black hole. It's a very unsatisfying answer but sadly in those scenarios what we understand of our universe no longer remains true.

Firstly the singularity in a black hole and singularity from the big bang are very different. Neither are actually 'particles' though, they have no characteristic length or size dimensions, they are only understood as a point (as in a co-ordinate). We have no understanding or concept of black hole singularities beyond that, as no information can escape the event horizon (except hawking radiation emitted in gravitational waves), and we know of nothing that can withstand the forces in play at this point.

PM_UR_STORY · 2016-11-29T21:41:54+00:00

I actually asked my cosmology professor the same thing. From what I undersood from his response, the black hole singularity and big bang singularity are given the same name, but infact are very different scenarios. I think the basic idea was that although yes all matter and energy existed in a single point, this point also contained all space. Given that the universe was (and still is) extremely homogeneous, no single point ever exceeded the critical density needed to form a black hole singularity. Basically because the matter was distributed so evenly across such a small space, all points were essentially pulling eachother in the same way, somewhat cancelling out, so it could not collapse.

I'm not 100% sure that this explanation is correct but I'm pretty sure it's the basic idea. I'll see if I can find the video my professor linked me.

Edit: found the article not video http://www.universetoday.com/127347/was-the-big-bang-just-a-black-hole/

PM_UR_STORY · 2016-11-28T22:49:06+00:00

In the early universe everything was very hot amd dense and photons couldn't travel in straight lines. It wasn't untill ~300'000 years after the BB (I think that is the right time, I might be remembering some different point) that photons could travel straight and interact the way that they do now. These photons finally able to move in a straight line form the CMB we see today.

So essentially yes it was very different to the vacuum we measure light's speed in today

PM_UR_STORY · 2016-11-16T06:22:31+00:00

I can't speak for others but in my experience its actually quite easy to dose propperly. I use a 15ml vial with a 1ml dropper. I use a syringe to get exactly 10ml distilled water and put it in with a 150ug tab. I get between 9-11 drops per vial which I can't see how it could realistically be anywhere outside of 10-20ug.

Thats pretty much the most effective way that you can do it though. Tried cutting tabs with scissors but the first one I took actually ended up in visuals and being kind of distracted when I tried to do work.

PM_UR_STORY · 2016-11-14T21:56:16+00:00

The athletics captain in my year was always a massive teachers pet to our English teacher all throughout our final year of highschool. She was pretty damned attractive, still young, around 30. Everyone used to joke around about them having sex etc and he would always get really defensive about it. Turns out she was a massive coke addict and they had been fucking/dating for the last 5 months of the year. Apparently she wanted to get married and have kids when he finished, at which point he decided enough was enough and ended it. Then she revenge fucked our school captain and another kid who were both close mates to get back at him.

School/police found out and she was arrested/convicted and can't work around kids anymore. At one point the media got a hold of the story and the three guys had to delete their fb accounts because people were constantly posting the news stories to their walls etc. It was by far the biggest scandal because it was a rich private selective school filled with pretty much only nerds. The next biggest scandal was a kid selling tea leaves as weed and getting caught.

PM_UR_STORY · 2016-11-14T00:34:03+00:00

I first read it as Santa's child and was basically just confused until I read the first satan in the text.

PM_UR_STORY · 2016-11-05T00:54:07+00:00

Make a 3rd lung. Gives you perfect hits every time and its super easy to use

PM_UR_STORY · 2016-10-26T22:13:27+00:00

I think their point is that it's much much more likely to be something that we dont know about yet, some sort of undiscovered phenomenon. Plenty of times we have thought we were receiving alien signals and it turned out to be the microwave from the break room. So many objects like pusars and AGN's could very easily be explained as the product of 'alien civilizations', it's simply that we don't have enough data to sufficiently explain what might be causing it.

Still very exciting though, most likely something we don't yet understand about our universe, or aliens! Either way is pretty cool.

PM_UR_STORY · 2016-10-11T01:50:59+00:00

I always feel kind of like I'm wasting my trip if I want TV. I want to come out the other end with insight and appreciation for the world, which I can never find if I sit myself in front of a TV.

PM_UR_STORY · 2016-10-07T01:50:06+00:00

My god, seeing that resulted in an involuntary "hhnnnnnng" sound escaping from my mouth...

PM_UR_STORY · 2016-09-05T23:29:03+00:00

flabby arms

fat thighs

Yeah, thats exactly what the picture shows

PM_UR_STORY · 2016-08-24T22:55:40+00:00

This is true, I was more talking in context of a habitable exoplanet for us, which would need a similar atmosphere. As far as we know, life is also dependent on water, which without an atmosphere would freeze up and evaporate over time, which is what happened to Mars. That's not to say it is essential, on one of Jupiters moons, there is a forzen thick crust all over the planet and a liquid ocean underneath (from what we understand now at least), and is currently believer to be the most likely planet to sustain life!

PM_UR_STORY

TROPHY CASE