MigL

Even if background checks are ( ever ) introduced, iNow, it'll only be for new gun sales. The large inventory of guns already in people's possession will most likely be 'grand-fathered' into the new regulations. IOW, a lot more people will die.

What the heck is the matter with you guys. Custard is for eating, not walking on !

And that's exactly what I've said all along, Strange. It may be just semantics, but... Those 'physically implausible properties' would make it extremely hard ( if not impossible ) to detect, much less 'de-bunk' and 'disprove', as another member claims. And IF it had those properties The M-M experiment would not have found a fringe shift no matter how accurate it was made. But the model seems to work just fine without a medium for EM waves so it is redundant ( not disproven ).

Congratulations Velocity_Boy. You posted evidence that the aether is not STATIONARY. How exactly does that 'de-bunk' the aether model ? ( sorry Moontanman, none of this answers your question, does it ? )

The only reason for the aether was to explain what EM actually 'waves'. All known waves were energetic deformations of a medium and so EMR was thought to need a medium to 'wave'. The properties of this medium would have added immeasurable complexity, and would make it undetectable. Relativity had none of this complexity ( ha ! ) and didn't require a medium for EM. So the aether became redundant.

Re-read the link you yourself posted... "One of the reasons for this position is that there is no direct experimental evidence for the existence of the ether - everything can be explained without it, hence the Occam's razor approach." ( fourth paragraph of the second article - The Mysterious Ether ) If you're gonna disagree with me, at least make it a challenge, and don't provide me with the information to defeat your argument.

The 'ripples' manifest themselves the same way that the 'curving' or 'warping' of space-time does. The co-ordinate system of the model describing these massive, energetic events predicts a 'ripple' spreading out from the event. We can finally detect these 'ripples' and they seem to agree with the predictions of the model ( that's HOW they were found ). That model is GR and it also suggests there is/are no preferred frames. I don't think the aether was ever exactly discredited. It just doesn't add anything, or explain anything further, to the model. It just adds unnecessary complexity, and is superfluous or redundant.

We've used EM astronomy for hundreds of years ( if not thousands ). We're just starting to use gravitational astronomy ( the only other long range effect ). It will take time and effort, but eventually it'll provide as much, if not more, information about the universe we live in.

Depends on your perspective Swansont... If you 're part of the 'bucket', 9000 is atrivial amount. If you're part of the 'drop' ( and their extended families ), its not trivial at all. And I agree on at least one of your points Rangerx, the only solution will come from Americans working together. Not 'finger pointing' and trying to place blame. That is what I would like to see discussed; Common ground between gun and anti gun advocates that provides a way forward and prevents mentally disturbed people ( or careless, or incompetent, etc. ) from getting a gun, and infringing on the right of their fellow citizens to live.

Ahh, but I'm not the one who claimed they were statistically rare, I'm not the one trying to excuse ISIS' actions because "someone else started it, and I'm not the one trying to 'scapegoat' a group of people ( conservatives ) for the actions of a mentally disturbed person, and the inactions of every American. That last point is what we are discussing, not American foreign policy ( there are plenty of threads for that )

"statistically, terrorists rarely kill anyone' ??? Well here's some statistics which come up as a first hit on Google... A UN report states that ISIS 'attacks deliberately and systematically target civilians', and in the first 8 months of 2014, more than 9000 people ( including women and children ) were killed, and more than 17000 were wounded. Is that a tolerable consequence ?

I agree swansont, and that's the first thing that needs to change. Country-wide rules for firearms purchases so you can't simply buy in another state. And a picture licensing system so others can't buy for you. This isn't the first time our freedoms have been eroded in the interest of safety, Ten oz. And you remember the old saying " your rights and freedoms stop when they start infringing on the rights of others "

Maybe not, but they should do their due diligence and check into any requirements before allowing the purchase. If they fail to do this and, subsequently, the unthinkable happens, they need to be charged with negligence.

I think DrP's is an excellent suggestion. Here in Ontario, Canada, a merchant can be fined and/or lose his licence to sell tobacco products if selling to minors. Similarly, bar owners can be charged if selling liquor to customers past the point of inebriation, and be held responsible for acts they commit while drunk. I don't see why a gun-shop owner is absolved of responsibility when selling to a ( subsequent ) murderer. Maybe background checks won't work by themselves, but may, in conjunction with other measures. Seems that if the tobacco/firearms people had a database which collects info from various governmental groups, the shooter may have passed his psych screening, but would have failed his security screening because of past actions.

I guess since its in the Political forum its become a political discussion. Some people seem more concerned with scoring political points for their favorite ideology, rather than discuss the real issue. This has nothing to do with 'conservative' terrorists or whatever other labels you want to attach to the gunman. Rather the fact that an obviously disturbed ( bipolar ? ) person was able to obtain and carry a dangerous firearm, and do so much damage. Even the fact that he identifies with ISIS is more than likely due to mental issues. And I'm sure someone will say if one of the club goers had been carrying, they could have defended themselves and stopped him, because that's always a good idea; A gun fight in a crowded club ??? The US has to start getting serious about the mental state and competence of the people they allow to purchase and carry firearms.

My bad, Imatfaal. I had confused it with the Chandrshekar ( sp ? ) limit, while this is the carbon/oxygen re-ignition mass, and subsequent runaway reaction. But could the presence of heavier nuclei in the core of recent/nearby white dwarfs produce a moderating effect on the reaction such that far-away Type 1A supernova are actually more luminous and farther away in comparison with near/recent ones.

IIRC, Zapatos, D. Trump said he'd make the Mexicans pay for the wall. It should then be simple enough to build the bamboo/thorn-bush wall on the Mexican side of the border so that THEY lose 2000 mi^2. ( ha-ha-ha ) Now I'm no fan of D.Trump by any stretch, but something has been going on which troubles me. At all his rallies and speeches there is invariably some incitement or act of aggression/violence by people demonstrating against him. This has to stop, You don't demonstrate the 'better way' by acting worse. He is disliked ( even hated ) by most Democrats and a lot of Republicans also, I've no doubt he'll implode before, or suffer a major defeat in, the election. But people protesting against him should keep the violence in check, or risk having the American electoral system become the laughing stock of even third world countries.

Just for consideration... A galaxy at great distance formed shortly after the Big Bang, would have stars composed of approx. 3/4 Hydrogen and 1/4 Helium as those were the available gases at the time. This star then proceeds to burn out and become a white dwarf with a ferrous, inactive core, but continues to accumulate mass from either a nearby star or a gaseous nebula through which it is travelling. This mass is in the form of Hydrogen/Helium. A close galaxy would have newer stars with a non trivial amount of heavy elements ( atomic weight greater than 26 ). When their core becomes ferrous and goes inactive at the white dwarf stage, they also continue to accumulate mass by the same method, but this additional mass also includes an appreciable amount of 'heavy' elements. Now when both distant and close stars reach a certain mass, they go Type 1A supernova before collapsing to a neutron star. My question is, do we know enough about the process ( and how differences manifest themselves ) to say that the recent ( close ) and long ago ( distant ) Type 1A events are equivalent ? And if not, could the 'differences' explain the accelerated expansion ?

Here's a simple way to look at it... Faster than c motion is allowed as long as there cannot be any information transfer. In the case of the two mountains separating or closing at 0.9c, any information is conveyed by them at only 0.9c ( not 1.8c ). Even though the 'apparent' separating or closing speed is greater than c. This same effect is observed in the motion of a shadow or an image on a surface. The image ( illuminated spot ) or shadowed spot, can be made to move across the surface superluminally. But no actual information is being transferred at a rate faster than c

Well, how about that ! Stealth coating technology already available to the masses. In a spray can, yet !

Hey !! Who says Canada's isn't an ideal climate already. We have all four seasons, spring , summer, fall AND winter. Not just summer all year round like the southern US, or 'dreary always', like the British isles.

Its not just the lower density of Hydrogen and Helium which explains their scarcity in Earth's atmosphere, as Sensei has explained. That would just lead to a 'stratification'. If the mean free velocity of a particle can exceed the escape velocity, then that particle/molecule can leave the Earth.. When the Sun first sparked up, its radiation was enough to 'blow' away all of mercury's atmosphere ( it being a small planet with low gravity. The next three planets lost only their lightest gaseous atmospheric elements, while the last four, being massive and distant ( cold >> low free velocity ) retained even Hydrogen/Helium

There's 'stuff' in Soylent too, Endy. "Its people ! Soylent Green is made out of people." C. Heston, best NRA member, ape fighter and Red Sea parter, ever.

How many children die because of a parent's negligence every year ? How many children die because parents expose them to 'unsafe' conditions ? How many make national news ? The fact that a gorilla had to be put down because a negligent parent exposed their kid to unsafe conditions, has made national news. Would there be this much discussion if the zoo staff had done nothing and the kid had been injured ( or killed ) ? I think the 'best' of the bad outcomes was chosen.

I have used, and still use hair gel on occasion ( when I'm getting fancy for a special occasion like a dinner/date ) but I've stopped coloring it. I'm starting to like the George Clooney, salt n' pepper look. You will get build-up after several uses, even shampooing daily. If using it daily, suggest using dishwashing soap like Palmolive, once a week to cut the build up. ( however,if your hair is thinning that may be too harsh ) Those other two guys are probably jealous, because they've lost their hair. But, I gotta ask, why are you asking this on a science forum ?