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Right, he is saying that the speed of light in both directions is the same with respect to any inertial frame as measured from that frame. So in the following example we have two observers. One standing along the tracks and the other traveling along the tracks in a railway car. Two flashes are emitted from two points along the tracks that are equal distance from the track observer. the light from these flashes arrive at the midpoint observer at the same moment as the railway observer is passing him. Thus both observers detect the light from the flashes at the same time. Like this: For the midpoint observer ( or anyone at rest with respect to the tracks) these flashes were emitted simultaneously, as shown by the expanding circles: However, for the railway car observer, events have to occur differently. He still detects the light from both flashes simultaneously, and they arrive when he is adjacent to the track observer. But unlike the track observer he has not remained halfway between the emission points the entire time. He is not an equal distance from the emission points when either of the flashes was emitted. But he must also measure the speed of light for each of the flashes as being the same relative to himself. But since the distances each of these flashes travel relative to him are not the same, in order for the light of the flashes to reach him simultaneously, they must have left at different times. And the sequence of the events for him occur like this: For the track observer, the flashes are emitted simultaneously, but for the railway observer they are not. This is the relativity of simultaneity: Events that are simultaneous in one inertial frame are not so according to another which in relative motion with respect to the first frame.

Hello everyone! It has been a while since I was active in the forum. Sure, I post a song here and there, but I just can't participate like I used to. I'm still having problems with my left hip even though I had a hip replacement back in April, 2017. Since then, I lost my job and medical insurance because I simply can't sit and write code for hours on end due to the extreme pain in my left hip. I lost my job as a software engineer in the middle of being treated by my doctor and they want a $500 deposit to continue treating me. Unfortunately, I don't have any income, I'm unable to work, and I've blown through my savings on living expenses and doctor bills. Most likely, I will need a revision done on my hip replacement to fix whatever is wrong so that I can go back to work and be a productive member of society. So, I'm reaching out to the community and asking for your help! The following link is to my GoFundMe campaign. I've attached photos of how my surgeries went so you will understand how much pain I'm actually experiencing. It's ok if you can't donate. You can help me out tremendously just by sharing this link! Every little bit helps!!! https://www.gofundme.com/clevelandraymond Thank you all so much! I truly appreciate anything you can do. Not only does your efforts mean the world to me, but also to my family as well.

! Moderator Note Daedelus approached us to coordinate this with the Admins and Mods. We've helped out a member in need before, so please feel free to participate (or not). We wish Daedelus the best of luck in funding his treatments. Thanks to everyone for spending your time here, in reasoned dialogue and intellectual honesty. SFN members are fantastic!

But while that may be nice for humans it can cause problems. For example, if it's not cold enough over winter certain pests may not be killed off, and that can damage crops - Italy has had problems with olives recently for this reason.

I live somewhere where half a degree is often the difference between frost and no frost on any given winter night - and perennial weeds that were kept in check by frosts can and are becoming rampant with warmer winters and fewer frosts. More labour, more cost for weed control. Around here the fire danger season starts sooner and finishes later with that "insignificant" half a degree of global average warming - and, significantly, the non-fire danger season is noticeably shorter. Burning during the cool season to reduce fuel loads is an important part of reducing the intensity and risks of out of control bushfires later - the opportunities for doing so are fewer and the risks of them escaping containment are increasing. More labour, more equipment requirements, more vigilance. The impacts of "hardly change at all" are actually very real. When I consider the likelihood of several more degrees I am legitimately alarmed. This relates to one of the questions I asked - "If where you live appears to benefit from global warming but other places suffer does that have any influence on your thinking?" Not irresponsible - looking at worst case scenarios is an essential part of risk management - although my own mention of 3-6 degrees of warming was not even looking at the worst case. I was asked for a citation for further temperatures rises reaching those levels and I gave one, and it showed the potential for higher temperatures than what I suggested. The 2000ppm CO2 levels probably is unrealistic - well, it is clearly labelled as an EXTREME scenario - but there are still influential people who do advocate maximising the use of fossil fuels, who want no limitations placed on their use, who want and expect all known reserves of fossil fuels to get used, which could indeed take it to that 2000ppm level - so scenarios for very high emissions continuing for the rest of this century are not impossibilities. A total breakdown of international agreements and internal policies to reign in emissions is something actively being campaigned for and undermining confidence in climate science has been a key theme being used to do so. I sort of presume views like Mistermack's, if widely shared by policy makers, would raise the likelihood of that, making "unlikely" and "extreme" scenarios more likely. If we don't end up with the extreme scenarios it will be in large part because of people taking the science on climate change seriously enough to seek and campaign for alternatives. One of the other themes of anti climate action campaigning is blaming the messengers - ie climate scientists and climate action advocates. Who is it labelling reasonable climate change proponents as alarmist? I suggest it is predominately people campaigning against strong climate action, as part of counter-messaging efforts to undermine overall confidence in all those expert studies and reports - who want the whole issue to be seen (falsely) as exaggeration. Suggesting we should try and avoid worst case scenarios (which, within those reports, are scenarios, not exaggerations) isn't what gets climate change proponents seen as alarmists, it is constant and widely disseminated counter-messaging claiming they are alarmists that is promoting the idea that they are alarmists. In the absence of constant counter-messaging what was in those reports - which is by any measure, genuinely alarming - would be much more likely to be taken seriously and acted upon. Which would, of course, make the extreme scenarios less likely. Organised opposition engaging in counter-messaging to prevent strong climate action has never been a reaction to irresponsible alarmist exaggeration, it is a response to the legitimately alarming mainstream expert advice. That opposition chose to do so for their own reasons - I think mostly responsibility avoidance although they may well have alarmed themselves with their own alarmist economic fears of going without fossil fuels.

Thank goodness you clarified this. I would never have known otherwise... Whoa, good catch. I need to refresh my math skills. I had know idea 1850 was only 70 years ago!

Well god has been called The Great Architect of the Universe. (Although that was a prod so maybe you don't count it)

The authors of that paper are known antivaccers in the Andrew Wakefield mould.

Francis.

So what is your criteria for deciding what is literal and what is not? Saying something took six days is meant to be figurative, but saying a virgin birth is meant to be literal? Sounds like you are cherry picking to meet your needs.

Agreed. They don't sound literal at all. And neither do virgin birth, rising from the dead, the Holy Trinity, turning bread and wine into the body and blood of Christ, or heaven and hell. Do you also agree those were not completely literal?

It is not quite as simple as that. More here: https://www.nist.gov/si-redefinition/kilogram-kibble-balance The mass is defined in terms of other factors that can all be measured independently of the mass: voltage, current, velocity and g (acceleration).

https://www.ligo.caltech.edu/news/ligo20180910 Jocelyn Bell Burnell Receives Breakthrough Prize News Release • September 10, 2018 The LIGO Lab and LIGO Scientific Collaboration are heartily congratulating Jocelyn Bell Burnell for becoming just the fourth recipient of the Special Breakthrough Prize in Fundamental Physics, a $3 million dollar prize bestowed to a scientist or group of scientists deemed to have made significant discoveries in or contributions to science. Burnell is being recognized for her astute observation of odd repeating ‘blips’ in radio telescope data gathered while she was a graduate student at Cambridge University in 1967. Initially, many believed these signals were man-made, but Burnell tenaciously followed up on the anomaly, proving that they were not of this Earth. The blips were later attributed to a then only-theorized exotic star called a radio pulsar. Pulsars are rotating neutron stars that emit a narrow beam of radio waves like a lighthouse. If the Earth is in the beam's path, we detect a radio pulse each time it sweeps across the Earth as the star itself rotates. Dr. Edward Witten, the chair of the selection committee said, in a statement released by the Breakthrough Prize Committee: “Jocelyn Bell Burnell’s discovery of pulsars will always stand as one of the great surprises in the history of astronomy. Until that moment, no one had any real idea how neutron stars could be observed, if indeed they existed. Suddenly it turned out that nature has provided an incredibly precise way to observe these objects, something that has led to many later advances.” Indeed, astronomers have continued to search for and study neutron stars in the cosmos, as they are excellent laboratories for studying general relativity and other extreme environs in the Universe. Coincidentally, at around the same time as Bell’s discovery, LIGO’s Rai Weiss, then MIT professor, was thinking about how astronomers could detect (also then only theoretical) gravitational waves, predicted to emanate from dense, massive objects like neutron stars. In fact, LIGO was specifically designed to detect gravitational waves from just the sort of objects that Bell Burnell discovered. Such a long-awaited event was finally observed last year, when LIGO and Virgo detected two colliding neutron stars. This discovery led to a paradigm shift in our understanding of the origins of heavy elements in the periodic table. LIGO continues to search for gravitational-wave ‘blips’ from neutron stars to complement the observations that Burnell made in radio signals. Without Burnell’s careful observation and persistence in alerting her thesis supervisor about the strange signals these mysterious objects and their treasure-trove of information about the Universe could have remained unknown to science for many years. Burnell is also being recognized for her “lifetime of inspiring scientific leadership”, according to the Breakthrough Prize committee. True to form, Burnell has decided to donate her entire $3 million prize to the United Kingdom’s Institute of Physics, to fund scholarships for students from groups underrepresented in science who want to study physics.

That's a global average I'm afraid. We've been smashing record highs each year locally but barely budging the average.

London drainage systems specifically aren’t equipped to handle the flooding, and it’s made worse since sewage systems so often intermingle with them and blow surplus water into the Thames.

I think he's just being smug in a joking way. Whatever the climate we have, we won't escape seal level rise.

Mistermack - if one degree C of global average warming looks good to you right now where you are, is that something you expect to be an enduring condition? Do you expect things to be just as good with 3 to 6 degrees - or to be even better? Or is that you do not expect that amount of warming can take place? If where you live appears to benefit from global warming but other places suffer does that have any influence on your thinking? Do you think what happens elsewhere will have no impact on UK prosperity or security? Whilst there are other contributors here I could ask questions like this I don't think I would get a civil discussion let alone answers. I am okay with lively discussion and disagreement but make no mistake, my own views unashamedly reflect the mainstream science based advice - which is not a matter of faith, but of trust in the institutions, practices and practitioners of science. I will say that I think your statement above trivialises the issues. We have had close to 30 years of consistent expert advice - unchanged by whether it was commissioned by Progressives or Conservatives (or however you want to label the 'sides'). I think that is a good indicator that the understanding of crucial climate processes is correct - but then, I am of the view that those reports and studies were competently done in good faith and genuinely represent what is known and not known.

Chemotaxis typically refers to a hard-wired response of sorts. It can be based on chemical pathways within a cell, but can also be a multicellular system that forms a circuit that reacts autonomously to chemical input. It is not usually used in contexts of e.g. learned avoidance. Thus it can be applied to multicellular organism but usually only in the context of hard-wired responses.

! Moderator Note Soapboxing and arguing in bad faith. No, we don't have to do this. Don't bring the topic up again.

Done is a synonym for complete in the way I used it, not actively in-progress or being implemented. I won’t belabor it, though How can a citation be provided for a question? Should Ken link to his own post?

What is this? Some kind of government cover-up? Is this supposed to be some kind of joke or prank or something? I stated this in my original post when I made this thread in the last line of the second paragraph. "This started to become a problem, because this was not the same equation that Einstein developed in his paper On the Electrodynamics of Moving Bodies, which was \[ t'=t \sqrt{1-v^2/c^2} \] ." It seems like I was unable to present the information in a way you could understand it more clearly or you failed to actually read it. I recommend you go over it and read it again, so you can see the significance of the derivations I was talking about and the actual point I was trying to make. I am simply showing a new derivation in Minkowski spacetime which has been unknown, and that is why text don't use this to explain relativity. Then they explain it using the light clock example which comes out to an inaccurate equation, which is not the same as Einsteins original equation in his paper, but the Lorentz Factor is the inverse of itself. If the object traveling were two spaceships and they launched a beacon at the starting line, they would come back to the beacon showing that both of their clocks no longer showed the same time as the beacon at the starting line or position, if the beacon just remained stationary the whole time. They would both observe each others time slow down as they are moving and this creates the Twin Paradox.

Do you believe that you have the right to create an organism that can never hide from predators, that thus can never have an evolutionary niche

So you believe that you have the right to to create whatever sick form of life that you choose for your pleasure..... Why do you imprison things Is looking at frogs in a tank fun

Bio luminescent frogs are not endangered. They are sad toys for sadder people

Bio luminescent frogs are not endangered unless you consider foolish peoples unethical experiments deserving of endangered species protection. I have hunting dogs that are never leashed and I let run free in national forest as often as I can. They also kill rabbits in my yard. They have never once been in an aquarium

Just because one can, does not mean one should