I don't think there are "anti-DM" people here outside of maybe a few wingnuts. There are lots of pro-evidence people here, myself included. The problem with dark matter is that there are at least three possible explanations, none of which have been conclusively ruled out. 1) Dark matter is indeed some form of matter as yet not fully understood, 2) Our measurements are in error somehow, and 3) our models for forces (gravity) are incorrect somehow.
I have a minor in applied physics so I'm not entirely uninformed though I'm not an expert. But I have yet to hear a single professional physicist clearly explain why we should favor the existence of dark matter as a preferable explanation to error in measurements or modeling errors. They seem to be strongly favoring dark matter being a real thing but all our "evidence" for it is indirect. It's perfectly reasonable that it might be explained by a better model similar to how relativity supplanted Newtonian mechanics. Invoking some form of exotic matter is perfectly reasonable too but the problem is that we have precisely zero direct measurements of such a thing. Until we do it's an open question.
but i thought the movement of galaxies WAS the expansion of the universe.
The movement of the galaxies can help us measure and observe the expansion of the universe but isn't the expansion itself. To use a simpler example, imagine a galaxy is an ant and that ant is standing on the surface of a balloon. The ant can walk around the balloon which is equivalent to the galaxies moving through space. Now inflate the balloon. The ant is moved because space (the balloon surface in this example) became larger but it wasn't because the ant itself moved. What happened is space expanded and everything in space moves a bit further apart as a result. But those objects in space (ants) are still free to move through space so the expansion of space doesn't explain everything we see by itself.
What we see is the galaxies moving (mostly) away from each other through space AND we see space expanding because they are moving away from each other faster than can be explained by simple movement through space. Space can expand faster than the speed of light because c is only the speed limit for matter moving through space. Space itself can expand arbitrarily fast as far as we know.
Dark matter certainly might exist. Or it might be measurement error. Or it might be model flaws. We simply aren't sure at this point. No one can say with any certainty that dark matter does not exist because the data isn't conclusive either way. Yes "dark matter" is something of a placeholder marketing term but it describes what appears to be a very real phenomena. There is some reasonable evidence to suggest dark matter is a real thing but none of it is conclusive at present. We have considerable confidence in some of our measurements so we have good reason to believe that measurement error is the least likely of the three possibilities. I've never heard a slam dunk explanation as to why we should favor dark matter being real over model error but I trust the professional physicists to sort it out in due course.
Dark matter is just the name of a theory that scientists have come up with to describe some anomalous gravity data they got when they looked at how the universe was put together mainly how galaxies interact with each other.
And that theory posits that there may be some form of matter we currently cannot directly observe. We don't know if that is the actual explanation but it's a necessity under current models if we presume they are correct.
In the Einstein universe, are they (matter & energy) not simply different states of the same thing?
Yes if one isn't being super pedantic. Your "states" analogy is reasonable. To say matter and energy are the same thing isn't exactly accurate but it's good enough for all but the most picky of purposes. But applying that relationship to so called dark matter and dark energy is a little bit fraught because we don't actually know what dark matter and dark energy are. As a result you are understandably conflating some things.
The terms "dark matter" and "dark energy" are sort of placeholder terms to explain some phenomena that we don't entirely understand yet and they are more marketing terms than precise terms of art. We don't actually know for certain that what we call "dark matter" is actually matter or that "dark energy" is actually energy. We just have some observations we haven't been able to adequately explain so we needed some short hand terms to explain what we are seeing in terms of the models we have. One of three things is happening. Either we are seeing something new, we are making measurement errors, or our models are wrong. Possibly some combination of all three.
Dark matter arises out of the fact that we see some observations that don't make sense based on the amount of baryonic ("normal") matter we can quantify. Our models of how gravity works tell us that for our observations to match our models there must be a lot more matter than we can see presuming our models are correct. So called dark energy arises out of our observations and measurements of the rate of expansion of the universe but it's even less well understood than dark matter.
Being that mass and energy rarely appear separately, would not the presence of 'dark energy' strongly infer the existence of 'dark matter'?
Mass is not the same thing as matter. You can have matter without mass such as with a photon. Mass is a property in some forms of matter, all of which move slower than c (the speed of light).
Just look for pictures of NYC at the turn of the century and you can see neighborhoods with hundreds of power and telephone lines from competing companies going through neighborhoods.
You kind of missed the point but I'll revise. There hasn't been any meaningful version of a free market in power line or wire line telecom or cable TV networks within the lifetime of anyone who will read this.
This is why it will never be that way again and why there should be no corporate interests invested in owning utility lines.
I don't see a problem with a (regulated) private company owning utility lines as long as they don't also own what is being transmitted over those same lines.
However, I have serious, fundamental reservations about government competing with the free market.
That might be a valid concern if provision of wireline data was actually a free market. It is not and never has been and there is no reasonable prospect of it becoming one in the near future either. Companies like AT&T and Comcast have a government granted monopoly because of the substantial capital costs involved in setting up and maintaining such a network. As such they need to be regulated to assure against abuses. Given that fact it is perfectly reasonable for the government to get into the market with alternative offerings if the private corporations are not providing sufficient value to the citizens.
You get the biggest, best-equipped military in the world.
Which we borrow every penny of funding for. Our deficit last year was $600 billion and so was our defense department budget. We borrowed literally every penny we spent on our military because we have a bunch of paranoid xenophobic republicans who break out in hives when they hear the word taxes. Heaven forbid we actually pay for the services we want...
You've done that at the expense of healthcare, education, and social programs. It's a choice you make every election cycle.
Some of us anyway. Personally I'm baffled how much of our country votes against their own self interest and is all to happy to burden their children with huge amounts of debt.
I was surprised to find that Canada pays less than the US overall.
You shouldn't be. Canada is rather more sanely managed than much of the US.
And for that Canada has a rudimentary universal health care system, and the US has what?
The US has a schizophrenic public/private system where nobody is in a position to control costs. We have universal health care but only for retired and some (but not all) poor people. We have great hospitals but nobody to keep costs in check. We refuse to insure millions of people thereby costing ourselves far more money when they inevitably show up in the emergency department of a hospital to get treated at far higher cost. We allow drug companies to charge whatever they want because... reasons. If you wanted to design a financially irresponsible health care system you'd have a hard time developing one more irresponsible than the one the US has.
Crumbling infrastructure and an overpriced military that funnels money into the military's suppliers and from there to the executives of those suppliers.
Our military isn't so much over priced as over funded. We have WAY more military than we could possibly justify or need. We spend more on our military than then next 8 largest military budgets combined, most of whom are allies. We have an annual federal deficit of $600 billion and guess how much we spent on our military last year? Yep, $600 billion. We basically borrow every penny we spend on the military, thereby screwing future generations because baby boomers are paranoid idiots.
I do certainly feel I get taxed MUCH more than what I get out of the system. Waaaay more.
We have a $600 Billion per year deficit as of 2016. You definitely aren't taxed more than the benefits that are doled out. Coincidentally our military budget last year was also right around $600 Billion so we could defund the military and make you whole if you want but it wouldn't lower your taxes a penny.
I don't think anyone thinks that America's income taxes straight out are that high.
Plenty of people believe this even though it demonstrably isn't true. Most of them call themselves republicans or libertarians. Hypocritically they don't actually want less of the things those taxes are supposed to cover (medicare, military, etc) but they are perfectly content to push the bill off to their children.
But now add in property taxes, which are very significant, social security, etc.
Add in all the other taxes you want but it's a trivial exercise to find countries that tax their citizens at a significantly higher rate than the US. On the other hand many of them get substantial benefits like health care and college tuition that we deny or overcharge our citizens for though privatization.
Why would people who own a tractor be living in Manhattan or nearby for?
Exactly my point. Not all services or companies benefit from high population density. That's why I used such an absurd example.
The example does not need to apply to NYC only because NYC is quite a unique case. Other big cities aren't lands that surrounded by water...
It's not unique to NYC at all though NYC may be a more extreme example than some. Driving into downtown Chicago for example can be hugely expensive and aggravating. Same with most large cities big enough to justify a robust public transit system.
My prediction is that within 10 years, half of new cars will have some level of self-driving ability. High-end cars will be almost all autonomous capable.
That's not exactly putting yourself out on a limb. That would be true if half of new cars got lane departure monitoring or adaptive cruise control. Like most new technology it's going to move both faster and slower than most people think. You'll see self-driving tech appearing in some vehicles but it's going to take quite a while to become ubiquitous. Some niches will probably move faster than others. Liability issues will hold things back. And development cycles are rather long in the auto industry and that isn't going to change.
Here's why it's going to take a while. Development cycles on new cars take 3-5 years and once in production cars don't change drastically for 4-8 years. Given that most cars under development right now do not have any meaningful self driving tech in them, you aren't going to see it start to seriously take off for another decade. I know this because I work in the industry and I know a fair bit about the cars we'll see in the next 3-5 years. Development of a car is a much more drawn out affair than most people realize. So you won't even see the tech start to arrive in a substantial way for another 5-10 years and it's going to take some time to get into the market place. 15-20 years is probably a more realistic time line to see mass adoption of self driving tech. There will be some niches that move faster but it's going to take a while.
This all assumes that the liability issues are worked out in a timely manner. It's not entirely clear how fast they will get sorted. It's also not clear how fast people will become comfortable with the new tech even if it works well and can be made available at an affordable cost.
I also predict that 1 or more of the classic "big 3" auto makers will go under or be purchased.
Always possible but you aren't basing that on evidence unless you are talking about FCA which has been bought and sold three times in the last 20 years. It's pretty unlikely Ford or GM will get bought because there simply aren't a lot of potential buyers given their size. It would require either some sort of catastrophe or some company like Apple with ludicrous amounts of cash decides to buy them. (Apple could buy both Ford and GM in cash if they wanted to but it would be a terrible idea for them to do it) Mergers on the other hand happen all the time. I could maybe see Ford or GM merging with another car company but otherwise it would take a company like Berkshire Hathaway to buy them and so far they haven't been interested.
People living there receive more services, and businesses located there get more customers
That depends on the services you are seeking and what sort of customers you are looking for. Good luck finding a tractor repair store or any customers for one in downtown Manhattan.
And nobody's forced to use a mode of transportation they dislike - you're allowed to walk, you can take a bus or train, or you can drive.
You can only drive in a city like NYC if you are rather wealthy. Costs too much and is far too impractical for most people. You essentially are forced to take public transit and not everyone likes that.
It's a win-win for everyone.
It's a win-win for people who want/need to be in a dense city. It's a huge loss for those who dislike living in such a place. Dense populations have their good and bad features. It's not a clear "win-win".
Mass transit does not appear to pay for itself on the surface, it pays for itself because of increase in population density that occurs as a result.
Sort of. Mass transit pays off biggest in cases where it allows you to use three dimensions instead of two. Subways allow you to use trains underground or overhead instead of on surface streets. Aircraft allow you to fly above the surface streets. When you get a dense city like NYC or Tokyo, you have people living in three dimensional buildings (high rises) but transiting in a two dimensional road network. This ensures congestion if you don't have a robust subway and tunnel network.
Busses obviously don't work in three dimensions but they can help optimize the 2D surface street usage. But above a certain population density they are limited in how much they can help. Street cars are basically trains on surface streets so they lack the routing flexibility of buses but don't take advantage of three dimensions like subways do so they really are a terrible solution for most circumstances as public transit.
Presently I cab buy 10 lightly used Leafs for the price of a Tesla, or 4 for the price of a Bolt. A used Leaf is the ideal way to ease into an EV.
That just indicates that they depreciate faster than milk goes bad. That's probably not a good thing. Cars that depreciate that fast generally do so for a reason so one has to ask the question why are they so cheap if they are such great cars? Second hand cars that sell at steep discounts generally do so because of serious flaws and lack of demand for them.
True but it is not an opinion unique to me. When enough people concur that it is ugly then it is de-facto ugly. I don't think I'd have a hard time finding a quorum of people who think the Leaf is not a particularly attractive vehicle aesthetically speaking. It has it's charms to be sure but external styling was clearly not a priority. The Tesla vehicles are supermodels by comparison. The Model S is a gorgeous car even if you completely ignore the fact that it is electric. I think you'll find that most people will say the Model 3 is FAR better looking than the Leaf.
Purchasing a Leaf can be a very practical decision for some people but nobody is buying it because they think it is drop dead beautiful to look at.
Correct me if I am wrong, but didn't much of that battery technology progress stagnate specifically from them mothballing the battery technology of the time capable of running an electric car and then banning them from being use in that?
I'm sure the lack of investment into battery tech by GM and others probably did stagnate matters though it's hard to put a number on how much since it didn't happen. One thing that is clear is that NiMh batteries were a dead end as far as electric vehicles were concerned. Too many problems with them. And as a result the EV1 was a dead end as well because an electric car is only as good as the battery tech in it. I've never seen any evidence that GM was seriously working on Li-Ion or other more advanced battery tech at the time of the EV1 and it certainly wasn't market ready at the time.
If it wasn't for them blocking it, that battery technology could have potentially come much sooner and we be further ahead than we are now.
Maybe but I'm not sure it really mattered much if true. The battery tech we use now (primarily Li-Ion) was already being worked on at the time so it's not entirely clear how much GM's activities could have accelerated the process or how much it held matters back. Maybe a lot, maybe not much. We'll never really know. My guess is that GM came in to the market too early. The EV1 was a vehicle with too many compromises to have been a game changer like the Model S has been. I'm also not sure if GM really could have brought pure EVs to market - I think there were too many competing forces within the company. Sort of a classic innovator's dilemma problem.
I've owned two Leafs. They are great cars, and you don't realize how great until you live with one.
I've driven one a fair bit and my brother-in-law owns one so I've spent enough time behind the wheel to get a good opinion. It's fine but all the stuff you are talking about as good features (which I don't dispute) are second order considerations. It has crap range and therefore it's mass market appeal is going to be limited. I'd buy a Chevy Bolt over a Leaf without question for the range alone. It also is a rather ugly vehicle from the outside. Most people don't care how nice the interior is if it doesn't get them where they need to go. They also won't buy it if they think it looks hideous. It mystifies me why so many EV makers insist on making intentionally ugly hatchbacks.
The Leaf is fine if your needs for a vehicle are decidedly limited and you don't car how it looks and you have access to a second car. But it isn't a great car in any general sense of the term. Double the range and it might become worth considering.
The range is absolutely fine for most people most of the time.
Most people don't want a vehicle that is fine "most of the time". Most want a vehicle that is fine ALL of the time. I exceed the range of a Leaf at least 4 times per month and sometimes more often. I seldom exceed the range of a Tesla or even a Chevy Bolt. The number of people willing to live with a 100 mile range is not a huge number.
And most people have access to more than one car - via a partner or family member.
So to buy a Leaf you have to periodically sponge off of someone else with a gas powered vehicle or own two cars. Fine if you have lots of money and forgiving friends but not a situation I want to be in personally. If I buy an EV it will have enough range that it is rarely going to be a problem. That means >200 miles minimum. I should be able to drive from Detroit to Cleveland without stopping. $30K+ for a vehicle that cannot do that is a rather stupid waste of money in my estimation.
The M3 will be fully self driving in time, just like the Model S and X.
Neither the Model S or Model X are self driving in any general sense of the term. Not yet anyway. No production car is. Presumably you are talking about autopilot which is the basis for what Tesla hopes will be full self driving features in the future. They have the hardware and some nifty features for some limited circumstances but that's not the same thing as being a self driving car.
Tesla has cars on the road, it's not vaporware company. His other companies are also progressing with their goals too.
Tesla hasn't made a sustained profit yet and it's still not clear if it is going to ultimately succeed as an ongoing enterprise. The fact that they've sold some product is nice but not sufficient. TSLA as a stock is wildly over valued given the likely prospects of the company in the next 10 years.
If you want to talk about something that took a lot of people's life savings and that was completely legal, let's talk about the fucking banks. Not only did they ruin people's lives but they also got more money for bailouts.
What the banks did is utterly irrelevant as to whether Tesla is a good investment or not. Your argument is nonsense. They have absolutely nothing to do with one another nor are they comparable.
The Leaf is a great car and they have done a lot to get people driving EVs, especially in Europe.
The Leaf is not a great car. It's a good enough car that proves there is demand for EVs but objectively it is a car with some very serious deficiencies. The worst deficiencies are that it's ugly and the range of the vehicle stinks. And before anyone repeats the meme about how far people drive in a day, it doesn't matter. If the car can't go at least 200-300 miles on a change then it is a crap car as far as the mass market is concerned in the current market. My brother-in-law has one and it's fine for a second commuter car but it's not a great car for most people.
The problem is that circumstances have kind of screwed them - Tesla's Model 3 is looking unbeatable right now, so far ahead of anything anyone else can offer it's stunning.
How do you figure? Sure it's got a lot of hype and interest but the Model 3 isn't even on the market yet. The Chevy Bolt has similar range and is apparently a pretty solid car and you can buy one today. Even the vaunted pre-orders for the Model 3 are misleading because it doesn't tell you much about what steady state demand for it will be. Once Telsa delivers the pent up demand to the true believers it's unclear what number they will sell on an ongoing basis. I hope they do well but we just don't know.
That big screen, full self driving if not from day one fairly early in its life, and best of all software updates in an age when most manufacturers can't keep the sat nav up to date.
The Model 3 will not be a self driving vehicle. It will have some technology to enable some of that but to call it a self driving car is not really accurate.
Large American car companies have been a cluster fuck since the 70s.
And yet people continue to buy their vehicles by the millions. I work in the industry and have for a lot of years. Fact is that the big US car companies are pretty well managed - they are at worst comparable to most of their competition. The problems they've had have mostly been legacy problems from back in the 80s and earlier when they didn't have as much competition. Primarily high labor and pension costs that they simply could not shed and that their competition was not subject to. US cars today are largely of good quality (with some exceptions) and all the US auto makers have managed to get their costs more competitive. FCA is still something of a mess but Ford and GM are pretty well managed and very profitable at the moment.
GM could have dominated this market starting with the EV1 years ago.
GM could have possible dominated the EV market but not with the EV1 and probably not its hypothetical successor either. They would have had to have a much longer investment horizon on EVs than was probably reasonable to expect. The EV1 was a nice enough little car if it happened to fit your needs but it was wildly impractical for most people (it was a two seater with very limited range) and hugely expensive to build. There was no way GM could have sold them profitably without huge government subsidies and it was never going to be a car with mass appeal. The battery pack in it only gave a range of 100 miles and the batteries on the last models were NiMh batteries with a capacity of 26.4kWh (a Tesla Model S has capacity 3-4X that amount). The EV1 routinely earns spots on worst car lists because it was a vehicle that relied on technology that just wasn't ready yet. EVs are only becoming practical now because of progress in battery technology.
Yeah, but that is one mistake that is easy to correct. Vote him out
"Easy to correct"? Not likely. Perhaps you are not aware of the fact that he can do a lot of damage in 4 years, much of which will take a long time to correct.
Vote him out, plus, farmers weren't the only ones who voted for 'The Donald' by a long shot.
No but let's not pretend he would have been elected without them. They voted directly contrary to their own self interest so I'm not oozing sympathy for any problems they incur as a result.
You could try to give big old JD some hard competition by importing tractors from places where they don't try to rape you over software updates but if you do 'The Donald' will slap a 30% import tariff on you so farmers are now literally fucked in every possible way.
Those same farmers evidently voted for Trump overwhelmingly so if they do get hit with an import tariff they have no right to complain. They knew the guy was a xenophobe and protectionist when they voted for him. They made their bed so they can sleep in it.
Only downside I can see is that those costs ultimately get passed along to you and me. Allowing JD to engage in this sort of shenanigans ultimately is paid for by us at the grocery store.
How much has tesla's supply chain on common with the other auto manuifacturer's.
Tesla is more vertically integrated than most. I've seen reports that they are around 80% vertically integrated. Problem is that ANY parts you have to get from outside suppliers can shut you down. I run a small manufacturing company that makes a tiny wire harness for some GM cars. It's not even a part that is critical to normal operation of the vehicle (hooks up a camera) but if we went bankrupt we conceivably could shut down one of GMs assembly lines. (the parts we supply have 14 week lead times due to some stupid design decisions by GM so they literally couldn't get them in a hurry) Most people don't realize just how fragile some of these supply chains really are.
So the short version is that every auto maker shares the same supply base to a significant degree. There are roughly 6 workers in the supply base for every one at the automakers and that doesn't count the companies that don't supply parts. So if GM went under they would take a LOT of suppliers with them. If the suppliers go under so will a number of other auto OEMs. If GM went under I'd expect both Ford and FCA to have a very hard time staying out of bankruptcy court. Probably several others as well.
Interestingly, GM used to be very vertically integrated and it was what made them the behemoth they are today. There can be a lot of value in being vertically integrated if you do it well and at sufficient scale. They seem to have forgotten that lesson. Of the big auto makers VW is probably the most vertically integrated with the Japanese makers just a bit behind. It's not that vertical integration is some cure-all magic formula for success but I think a lot of companies forgot about the big picture over time.
I would expect its much less than the others since the tech is all different.
The power train tech is different but the chassis, body, interior, wheels, etc are all very conventional and not much different at all from their competitors. They smartly produce as much as they can in house but there is not much unique outside of how they propel the vehicle and the software to run everything. There are some things they simply cannot do in house. Honestly if Tesla didn't vertically integrate I don't think they would have a prayer of surviving. They would be beholden to a bunch of auto suppliers who are (revenue wise) much larger than Tesla is and Tesla doesn't do enough volume to really control them. GM can get away with less vertical integration because they are big enough to crush suppliers who don't dance to their tune.
Comcast announced Xfinity Mobile on Thursday, a new wireless service that will be available for its nearly 25 million broadband customers
Not a way in hell I would use Comcast for mobile. I'm stuck with them for wired internet at home but it's not like they've earned any love from me there. And combining them with Verizon? If they think that makes it better they are using some heavy drugs.
Slashdot Mirror
There appears to be a whole anti-DM subculture.
I don't think there are "anti-DM" people here outside of maybe a few wingnuts. There are lots of pro-evidence people here, myself included. The problem with dark matter is that there are at least three possible explanations, none of which have been conclusively ruled out. 1) Dark matter is indeed some form of matter as yet not fully understood, 2) Our measurements are in error somehow, and 3) our models for forces (gravity) are incorrect somehow.
I have a minor in applied physics so I'm not entirely uninformed though I'm not an expert. But I have yet to hear a single professional physicist clearly explain why we should favor the existence of dark matter as a preferable explanation to error in measurements or modeling errors. They seem to be strongly favoring dark matter being a real thing but all our "evidence" for it is indirect. It's perfectly reasonable that it might be explained by a better model similar to how relativity supplanted Newtonian mechanics. Invoking some form of exotic matter is perfectly reasonable too but the problem is that we have precisely zero direct measurements of such a thing. Until we do it's an open question.
but i thought the movement of galaxies WAS the expansion of the universe.
The movement of the galaxies can help us measure and observe the expansion of the universe but isn't the expansion itself. To use a simpler example, imagine a galaxy is an ant and that ant is standing on the surface of a balloon. The ant can walk around the balloon which is equivalent to the galaxies moving through space. Now inflate the balloon. The ant is moved because space (the balloon surface in this example) became larger but it wasn't because the ant itself moved. What happened is space expanded and everything in space moves a bit further apart as a result. But those objects in space (ants) are still free to move through space so the expansion of space doesn't explain everything we see by itself.
What we see is the galaxies moving (mostly) away from each other through space AND we see space expanding because they are moving away from each other faster than can be explained by simple movement through space. Space can expand faster than the speed of light because c is only the speed limit for matter moving through space. Space itself can expand arbitrarily fast as far as we know.
Dark matter does not exist
Dark matter certainly might exist. Or it might be measurement error. Or it might be model flaws. We simply aren't sure at this point. No one can say with any certainty that dark matter does not exist because the data isn't conclusive either way. Yes "dark matter" is something of a placeholder marketing term but it describes what appears to be a very real phenomena. There is some reasonable evidence to suggest dark matter is a real thing but none of it is conclusive at present. We have considerable confidence in some of our measurements so we have good reason to believe that measurement error is the least likely of the three possibilities. I've never heard a slam dunk explanation as to why we should favor dark matter being real over model error but I trust the professional physicists to sort it out in due course.
Dark matter is just the name of a theory that scientists have come up with to describe some anomalous gravity data they got when they looked at how the universe was put together mainly how galaxies interact with each other.
And that theory posits that there may be some form of matter we currently cannot directly observe. We don't know if that is the actual explanation but it's a necessity under current models if we presume they are correct.
In the Einstein universe, are they (matter & energy) not simply different states of the same thing?
Yes if one isn't being super pedantic. Your "states" analogy is reasonable. To say matter and energy are the same thing isn't exactly accurate but it's good enough for all but the most picky of purposes. But applying that relationship to so called dark matter and dark energy is a little bit fraught because we don't actually know what dark matter and dark energy are. As a result you are understandably conflating some things.
The terms "dark matter" and "dark energy" are sort of placeholder terms to explain some phenomena that we don't entirely understand yet and they are more marketing terms than precise terms of art. We don't actually know for certain that what we call "dark matter" is actually matter or that "dark energy" is actually energy. We just have some observations we haven't been able to adequately explain so we needed some short hand terms to explain what we are seeing in terms of the models we have. One of three things is happening. Either we are seeing something new, we are making measurement errors, or our models are wrong. Possibly some combination of all three.
Dark matter arises out of the fact that we see some observations that don't make sense based on the amount of baryonic ("normal") matter we can quantify. Our models of how gravity works tell us that for our observations to match our models there must be a lot more matter than we can see presuming our models are correct. So called dark energy arises out of our observations and measurements of the rate of expansion of the universe but it's even less well understood than dark matter.
Being that mass and energy rarely appear separately, would not the presence of 'dark energy' strongly infer the existence of 'dark matter'?
Mass is not the same thing as matter. You can have matter without mass such as with a photon. Mass is a property in some forms of matter, all of which move slower than c (the speed of light).
Just look for pictures of NYC at the turn of the century and you can see neighborhoods with hundreds of power and telephone lines from competing companies going through neighborhoods.
You kind of missed the point but I'll revise. There hasn't been any meaningful version of a free market in power line or wire line telecom or cable TV networks within the lifetime of anyone who will read this.
This is why it will never be that way again and why there should be no corporate interests invested in owning utility lines.
I don't see a problem with a (regulated) private company owning utility lines as long as they don't also own what is being transmitted over those same lines.
However, I have serious, fundamental reservations about government competing with the free market.
That might be a valid concern if provision of wireline data was actually a free market. It is not and never has been and there is no reasonable prospect of it becoming one in the near future either. Companies like AT&T and Comcast have a government granted monopoly because of the substantial capital costs involved in setting up and maintaining such a network. As such they need to be regulated to assure against abuses. Given that fact it is perfectly reasonable for the government to get into the market with alternative offerings if the private corporations are not providing sufficient value to the citizens.
You get the biggest, best-equipped military in the world.
Which we borrow every penny of funding for. Our deficit last year was $600 billion and so was our defense department budget. We borrowed literally every penny we spent on our military because we have a bunch of paranoid xenophobic republicans who break out in hives when they hear the word taxes. Heaven forbid we actually pay for the services we want...
You've done that at the expense of healthcare, education, and social programs. It's a choice you make every election cycle.
Some of us anyway. Personally I'm baffled how much of our country votes against their own self interest and is all to happy to burden their children with huge amounts of debt.
I was surprised to find that Canada pays less than the US overall.
You shouldn't be. Canada is rather more sanely managed than much of the US.
And for that Canada has a rudimentary universal health care system, and the US has what?
The US has a schizophrenic public/private system where nobody is in a position to control costs. We have universal health care but only for retired and some (but not all) poor people. We have great hospitals but nobody to keep costs in check. We refuse to insure millions of people thereby costing ourselves far more money when they inevitably show up in the emergency department of a hospital to get treated at far higher cost. We allow drug companies to charge whatever they want because... reasons. If you wanted to design a financially irresponsible health care system you'd have a hard time developing one more irresponsible than the one the US has.
Crumbling infrastructure and an overpriced military that funnels money into the military's suppliers and from there to the executives of those suppliers.
Our military isn't so much over priced as over funded. We have WAY more military than we could possibly justify or need. We spend more on our military than then next 8 largest military budgets combined, most of whom are allies. We have an annual federal deficit of $600 billion and guess how much we spent on our military last year? Yep, $600 billion. We basically borrow every penny we spend on the military, thereby screwing future generations because baby boomers are paranoid idiots.
I do certainly feel I get taxed MUCH more than what I get out of the system. Waaaay more.
We have a $600 Billion per year deficit as of 2016. You definitely aren't taxed more than the benefits that are doled out. Coincidentally our military budget last year was also right around $600 Billion so we could defund the military and make you whole if you want but it wouldn't lower your taxes a penny.
I don't think anyone thinks that America's income taxes straight out are that high.
Plenty of people believe this even though it demonstrably isn't true. Most of them call themselves republicans or libertarians. Hypocritically they don't actually want less of the things those taxes are supposed to cover (medicare, military, etc) but they are perfectly content to push the bill off to their children.
But now add in property taxes, which are very significant, social security, etc.
Add in all the other taxes you want but it's a trivial exercise to find countries that tax their citizens at a significantly higher rate than the US. On the other hand many of them get substantial benefits like health care and college tuition that we deny or overcharge our citizens for though privatization.
Why would people who own a tractor be living in Manhattan or nearby for?
Exactly my point. Not all services or companies benefit from high population density. That's why I used such an absurd example.
The example does not need to apply to NYC only because NYC is quite a unique case. Other big cities aren't lands that surrounded by water...
It's not unique to NYC at all though NYC may be a more extreme example than some. Driving into downtown Chicago for example can be hugely expensive and aggravating. Same with most large cities big enough to justify a robust public transit system.
My prediction is that within 10 years, half of new cars will have some level of self-driving ability. High-end cars will be almost all autonomous capable.
That's not exactly putting yourself out on a limb. That would be true if half of new cars got lane departure monitoring or adaptive cruise control. Like most new technology it's going to move both faster and slower than most people think. You'll see self-driving tech appearing in some vehicles but it's going to take quite a while to become ubiquitous. Some niches will probably move faster than others. Liability issues will hold things back. And development cycles are rather long in the auto industry and that isn't going to change.
Here's why it's going to take a while. Development cycles on new cars take 3-5 years and once in production cars don't change drastically for 4-8 years. Given that most cars under development right now do not have any meaningful self driving tech in them, you aren't going to see it start to seriously take off for another decade. I know this because I work in the industry and I know a fair bit about the cars we'll see in the next 3-5 years. Development of a car is a much more drawn out affair than most people realize. So you won't even see the tech start to arrive in a substantial way for another 5-10 years and it's going to take some time to get into the market place. 15-20 years is probably a more realistic time line to see mass adoption of self driving tech. There will be some niches that move faster but it's going to take a while.
This all assumes that the liability issues are worked out in a timely manner. It's not entirely clear how fast they will get sorted. It's also not clear how fast people will become comfortable with the new tech even if it works well and can be made available at an affordable cost.
I also predict that 1 or more of the classic "big 3" auto makers will go under or be purchased.
Always possible but you aren't basing that on evidence unless you are talking about FCA which has been bought and sold three times in the last 20 years. It's pretty unlikely Ford or GM will get bought because there simply aren't a lot of potential buyers given their size. It would require either some sort of catastrophe or some company like Apple with ludicrous amounts of cash decides to buy them. (Apple could buy both Ford and GM in cash if they wanted to but it would be a terrible idea for them to do it) Mergers on the other hand happen all the time. I could maybe see Ford or GM merging with another car company but otherwise it would take a company like Berkshire Hathaway to buy them and so far they haven't been interested.
People living there receive more services, and businesses located there get more customers
That depends on the services you are seeking and what sort of customers you are looking for. Good luck finding a tractor repair store or any customers for one in downtown Manhattan.
And nobody's forced to use a mode of transportation they dislike - you're allowed to walk, you can take a bus or train, or you can drive.
You can only drive in a city like NYC if you are rather wealthy. Costs too much and is far too impractical for most people. You essentially are forced to take public transit and not everyone likes that.
It's a win-win for everyone.
It's a win-win for people who want/need to be in a dense city. It's a huge loss for those who dislike living in such a place. Dense populations have their good and bad features. It's not a clear "win-win".
Mass transit does not appear to pay for itself on the surface, it pays for itself because of increase in population density that occurs as a result.
Sort of. Mass transit pays off biggest in cases where it allows you to use three dimensions instead of two. Subways allow you to use trains underground or overhead instead of on surface streets. Aircraft allow you to fly above the surface streets. When you get a dense city like NYC or Tokyo, you have people living in three dimensional buildings (high rises) but transiting in a two dimensional road network. This ensures congestion if you don't have a robust subway and tunnel network.
Busses obviously don't work in three dimensions but they can help optimize the 2D surface street usage. But above a certain population density they are limited in how much they can help. Street cars are basically trains on surface streets so they lack the routing flexibility of buses but don't take advantage of three dimensions like subways do so they really are a terrible solution for most circumstances as public transit.
Presently I cab buy 10 lightly used Leafs for the price of a Tesla, or 4 for the price of a Bolt. A used Leaf is the ideal way to ease into an EV.
That just indicates that they depreciate faster than milk goes bad. That's probably not a good thing. Cars that depreciate that fast generally do so for a reason so one has to ask the question why are they so cheap if they are such great cars? Second hand cars that sell at steep discounts generally do so because of serious flaws and lack of demand for them.
Your point that the LEAF is "ugly" is an opinion.
True but it is not an opinion unique to me. When enough people concur that it is ugly then it is de-facto ugly. I don't think I'd have a hard time finding a quorum of people who think the Leaf is not a particularly attractive vehicle aesthetically speaking. It has it's charms to be sure but external styling was clearly not a priority. The Tesla vehicles are supermodels by comparison. The Model S is a gorgeous car even if you completely ignore the fact that it is electric. I think you'll find that most people will say the Model 3 is FAR better looking than the Leaf.
Purchasing a Leaf can be a very practical decision for some people but nobody is buying it because they think it is drop dead beautiful to look at.
Correct me if I am wrong, but didn't much of that battery technology progress stagnate specifically from them mothballing the battery technology of the time capable of running an electric car and then banning them from being use in that?
I'm sure the lack of investment into battery tech by GM and others probably did stagnate matters though it's hard to put a number on how much since it didn't happen. One thing that is clear is that NiMh batteries were a dead end as far as electric vehicles were concerned. Too many problems with them. And as a result the EV1 was a dead end as well because an electric car is only as good as the battery tech in it. I've never seen any evidence that GM was seriously working on Li-Ion or other more advanced battery tech at the time of the EV1 and it certainly wasn't market ready at the time.
If it wasn't for them blocking it, that battery technology could have potentially come much sooner and we be further ahead than we are now.
Maybe but I'm not sure it really mattered much if true. The battery tech we use now (primarily Li-Ion) was already being worked on at the time so it's not entirely clear how much GM's activities could have accelerated the process or how much it held matters back. Maybe a lot, maybe not much. We'll never really know. My guess is that GM came in to the market too early. The EV1 was a vehicle with too many compromises to have been a game changer like the Model S has been. I'm also not sure if GM really could have brought pure EVs to market - I think there were too many competing forces within the company. Sort of a classic innovator's dilemma problem.
I've owned two Leafs. They are great cars, and you don't realize how great until you live with one.
I've driven one a fair bit and my brother-in-law owns one so I've spent enough time behind the wheel to get a good opinion. It's fine but all the stuff you are talking about as good features (which I don't dispute) are second order considerations. It has crap range and therefore it's mass market appeal is going to be limited. I'd buy a Chevy Bolt over a Leaf without question for the range alone. It also is a rather ugly vehicle from the outside. Most people don't care how nice the interior is if it doesn't get them where they need to go. They also won't buy it if they think it looks hideous. It mystifies me why so many EV makers insist on making intentionally ugly hatchbacks.
The Leaf is fine if your needs for a vehicle are decidedly limited and you don't car how it looks and you have access to a second car. But it isn't a great car in any general sense of the term. Double the range and it might become worth considering.
The range is absolutely fine for most people most of the time.
Most people don't want a vehicle that is fine "most of the time". Most want a vehicle that is fine ALL of the time. I exceed the range of a Leaf at least 4 times per month and sometimes more often. I seldom exceed the range of a Tesla or even a Chevy Bolt. The number of people willing to live with a 100 mile range is not a huge number.
And most people have access to more than one car - via a partner or family member.
So to buy a Leaf you have to periodically sponge off of someone else with a gas powered vehicle or own two cars. Fine if you have lots of money and forgiving friends but not a situation I want to be in personally. If I buy an EV it will have enough range that it is rarely going to be a problem. That means >200 miles minimum. I should be able to drive from Detroit to Cleveland without stopping. $30K+ for a vehicle that cannot do that is a rather stupid waste of money in my estimation.
The M3 will be fully self driving in time, just like the Model S and X.
Neither the Model S or Model X are self driving in any general sense of the term. Not yet anyway. No production car is. Presumably you are talking about autopilot which is the basis for what Tesla hopes will be full self driving features in the future. They have the hardware and some nifty features for some limited circumstances but that's not the same thing as being a self driving car.
Tesla has cars on the road, it's not vaporware company. His other companies are also progressing with their goals too.
Tesla hasn't made a sustained profit yet and it's still not clear if it is going to ultimately succeed as an ongoing enterprise. The fact that they've sold some product is nice but not sufficient. TSLA as a stock is wildly over valued given the likely prospects of the company in the next 10 years.
If you want to talk about something that took a lot of people's life savings and that was completely legal, let's talk about the fucking banks. Not only did they ruin people's lives but they also got more money for bailouts.
What the banks did is utterly irrelevant as to whether Tesla is a good investment or not. Your argument is nonsense. They have absolutely nothing to do with one another nor are they comparable.
The Leaf is a great car and they have done a lot to get people driving EVs, especially in Europe.
The Leaf is not a great car. It's a good enough car that proves there is demand for EVs but objectively it is a car with some very serious deficiencies. The worst deficiencies are that it's ugly and the range of the vehicle stinks. And before anyone repeats the meme about how far people drive in a day, it doesn't matter. If the car can't go at least 200-300 miles on a change then it is a crap car as far as the mass market is concerned in the current market. My brother-in-law has one and it's fine for a second commuter car but it's not a great car for most people.
The problem is that circumstances have kind of screwed them - Tesla's Model 3 is looking unbeatable right now, so far ahead of anything anyone else can offer it's stunning.
How do you figure? Sure it's got a lot of hype and interest but the Model 3 isn't even on the market yet. The Chevy Bolt has similar range and is apparently a pretty solid car and you can buy one today. Even the vaunted pre-orders for the Model 3 are misleading because it doesn't tell you much about what steady state demand for it will be. Once Telsa delivers the pent up demand to the true believers it's unclear what number they will sell on an ongoing basis. I hope they do well but we just don't know.
That big screen, full self driving if not from day one fairly early in its life, and best of all software updates in an age when most manufacturers can't keep the sat nav up to date.
The Model 3 will not be a self driving vehicle. It will have some technology to enable some of that but to call it a self driving car is not really accurate.
Large American car companies have been a cluster fuck since the 70s.
And yet people continue to buy their vehicles by the millions. I work in the industry and have for a lot of years. Fact is that the big US car companies are pretty well managed - they are at worst comparable to most of their competition. The problems they've had have mostly been legacy problems from back in the 80s and earlier when they didn't have as much competition. Primarily high labor and pension costs that they simply could not shed and that their competition was not subject to. US cars today are largely of good quality (with some exceptions) and all the US auto makers have managed to get their costs more competitive. FCA is still something of a mess but Ford and GM are pretty well managed and very profitable at the moment.
GM could have dominated this market starting with the EV1 years ago.
GM could have possible dominated the EV market but not with the EV1 and probably not its hypothetical successor either. They would have had to have a much longer investment horizon on EVs than was probably reasonable to expect. The EV1 was a nice enough little car if it happened to fit your needs but it was wildly impractical for most people (it was a two seater with very limited range) and hugely expensive to build. There was no way GM could have sold them profitably without huge government subsidies and it was never going to be a car with mass appeal. The battery pack in it only gave a range of 100 miles and the batteries on the last models were NiMh batteries with a capacity of 26.4kWh (a Tesla Model S has capacity 3-4X that amount). The EV1 routinely earns spots on worst car lists because it was a vehicle that relied on technology that just wasn't ready yet. EVs are only becoming practical now because of progress in battery technology.
Yeah, but that is one mistake that is easy to correct. Vote him out
"Easy to correct"? Not likely. Perhaps you are not aware of the fact that he can do a lot of damage in 4 years, much of which will take a long time to correct.
Vote him out, plus, farmers weren't the only ones who voted for 'The Donald' by a long shot.
No but let's not pretend he would have been elected without them. They voted directly contrary to their own self interest so I'm not oozing sympathy for any problems they incur as a result.
You could try to give big old JD some hard competition by importing tractors from places where they don't try to rape you over software updates but if you do 'The Donald' will slap a 30% import tariff on you so farmers are now literally fucked in every possible way.
Those same farmers evidently voted for Trump overwhelmingly so if they do get hit with an import tariff they have no right to complain. They knew the guy was a xenophobe and protectionist when they voted for him. They made their bed so they can sleep in it.
Only downside I can see is that those costs ultimately get passed along to you and me. Allowing JD to engage in this sort of shenanigans ultimately is paid for by us at the grocery store.
How much has tesla's supply chain on common with the other auto manuifacturer's.
Tesla is more vertically integrated than most. I've seen reports that they are around 80% vertically integrated. Problem is that ANY parts you have to get from outside suppliers can shut you down. I run a small manufacturing company that makes a tiny wire harness for some GM cars. It's not even a part that is critical to normal operation of the vehicle (hooks up a camera) but if we went bankrupt we conceivably could shut down one of GMs assembly lines. (the parts we supply have 14 week lead times due to some stupid design decisions by GM so they literally couldn't get them in a hurry) Most people don't realize just how fragile some of these supply chains really are.
So the short version is that every auto maker shares the same supply base to a significant degree. There are roughly 6 workers in the supply base for every one at the automakers and that doesn't count the companies that don't supply parts. So if GM went under they would take a LOT of suppliers with them. If the suppliers go under so will a number of other auto OEMs. If GM went under I'd expect both Ford and FCA to have a very hard time staying out of bankruptcy court. Probably several others as well.
Interestingly, GM used to be very vertically integrated and it was what made them the behemoth they are today. There can be a lot of value in being vertically integrated if you do it well and at sufficient scale. They seem to have forgotten that lesson. Of the big auto makers VW is probably the most vertically integrated with the Japanese makers just a bit behind. It's not that vertical integration is some cure-all magic formula for success but I think a lot of companies forgot about the big picture over time.
I would expect its much less than the others since the tech is all different.
The power train tech is different but the chassis, body, interior, wheels, etc are all very conventional and not much different at all from their competitors. They smartly produce as much as they can in house but there is not much unique outside of how they propel the vehicle and the software to run everything. There are some things they simply cannot do in house. Honestly if Tesla didn't vertically integrate I don't think they would have a prayer of surviving. They would be beholden to a bunch of auto suppliers who are (revenue wise) much larger than Tesla is and Tesla doesn't do enough volume to really control them. GM can get away with less vertical integration because they are big enough to crush suppliers who don't dance to their tune.
Comcast announced Xfinity Mobile on Thursday, a new wireless service that will be available for its nearly 25 million broadband customers
Not a way in hell I would use Comcast for mobile. I'm stuck with them for wired internet at home but it's not like they've earned any love from me there. And combining them with Verizon? If they think that makes it better they are using some heavy drugs.