Talk:Maglev

Southwest Jiaotong University, China

This subsection contains the following:

On December 31, 2000, the first crewed high-temperature superconducting maglev was tested successfully at Southwest Jiaotong University, Chengdu, China. This system is based on the principle that bulk high-temperature superconductors can be levitated or suspended stably above or below a permanent magnet. The load was over 530 kg (1166 lb) and the levitation gap over 20 mm (0.79 in). The system uses liquid nitrogen, which is very cheap, to cool the superconductor.

I'm baffled by this. I don't know whether this is a mistranslation or what, but I do know that you cannot use liquid nitrogen to cool something to a high temperature. Unfortunately there is no cite to go to for clarification, so I've added a cite needed tag.

I'm rather tempted to delete the whole section as patent nonsense, but something about it suggests that there is more to it than that. So I'll hold fire for a while and see if anybody reacts to the tag. If not, it is toast. -- Starbois (talk) 11:18, 18 June 2010 (UTC)

Wondering whether cooling can achieve high temperature? Say it's a winter afternoon. The temperature outside is at a maximum ('high') of, say, zero degrees Celsius. Now you put a glass of warm water outside while the temperature is as high as it ever was that day. Now will water at room temperature "cool" to the wintertime high or *warm to that temperature? 02:13, 26 September 2010 (UTC)LeucineZIpper —Preceding unsigned comment added by 24.184.234.24 (talk) 02:17, 26 September 2010 (UTC)LeucineZipper

In this case, "high temperature" is referring specifically to superconductors. A "high-temperature superconductor" is one that uses temperatures that are relatively much higher than the ones we have been using. They are still very cold "liquid nitrogen" temperatures, but "high-temperature superconductor" is a technical term used to separate new magnet technologies from the old ones. -- Dmitry Murashchik —Preceding unsigned comment added by 167.102.22.42 (talk) 17:37, 21 October 2010 (UTC)

[It doesn't say it cools something to a high temperature, even isolating the final sentence from its context. It couldn't be clearer to a native English reader. JohndanR (talk) 16:09, 19 January 2024 (UTC)]

T-Flight Does Not Qualify as Train

I've reverted recent edits which updated the train speed record to T-Flight as I don't believe the T-Flight qualifies as a train. In Railway speed record, "trains" are assumed to mean "Passenger trains", but the T-Flight vehicle appears in pictures to be about the size of a car and unable to carry passengers. Furthermore, the 623 km/h speed record was achieved on just 2km of track. This would have required acceleration/deceleration of over 1g, which in my opinion, makes the T-Flight more comparable to a rocket sled.

As a point of comparison, the previously listed speed record was achieved by the L0 Series Shinkansen while carrying passengers in a 7 car set which was at least 170m long. 219.89.31.196 (talk) 03:59, 16 March 2024 (UTC)

Economics

I am not convinced by the economics section of the article as it seems to aim at manipulating the reader into thinking the Maglev is the best solution for the future of train. No comparison of cost per km/trip, payload, maintenance, installation cost compare to a traditional system… 2604:3D09:A176:E300:8814:E80E:D46D:ED65 (talk) 14:01, 1 June 2024 (UTC)

1917 Maglev video?

I've ran into this Video on YouTube depicting something looking like a scaled up Bachelet's model. It's dated 1917 and filmed in an English-speaking country. I hope it would be usefull. Dieſelmaus (talk) 08:07, 27 July 2024 (UTC)

M-Bahn

I came across the article on this and thought a summary would be a useful addition here; it was then deleted with the edit note "Rv interesting but unsourced addition; could you re-add this with appropriate sources, please?".
So, what is the problem here? The information is from the introduction of the linked article, which (I would have thought) should be verification enough: Or, if anyone feels more is needed, it is customary to add a citation request tag, or (in the spirit of co-operation and general improvement) add what is felt necessary from that article. Contrariwise, if the information is believed to be wrong, the problem lies with the linked article also, and should have been addressed there (it wasn’t). So what was it about this that warranted total deletion? Moonraker12 (talk) 23:20, 30 September 2024 (UTC)

Hello, Moonraker, thanks for asking about this. There are actually two concerns I have with your addition, only one of which I saw at the time. That first issue is simply verifiability, one of Wikipedia's policies. Without any citations, it's hard for any reader to verify that paragraph. Indeed, it looked to me, when I saw it, to be just some text some person made up. The fact that you took it from another article was non-evident and, in any case, an inadequate excuse; readers should not have to do a scavenger hunt to find reliable sources through which they can verify our claims. And of course, Wikipedia itself is not a reliable source (even if you had cited the M-Bahn page).

As it happens, and since you mention the idea that the problem lies with the linked article also, and should have been addressed there, the text you copied was from the lede, where we generally try to avoid including citations (see MOS:LEADCITE). So there's not necessarily a problem with M-Bahn (although I haven't read more than the lead paragraph); the (first) problem is with lack of supporting citations in the text you pasted here.

But I said there was a second issue, which I had not noticed at the time of my reversion. It is that you copied, verbatim, content from another page. I won't write at great detail on this, but will point you to the somewhat lengthy text at Wikipedia:Copying within Wikipedia. There was no indication to me that you were copying text from somewhere else. A quick reversion seemed the best approach.

But my edit summary included, as you note above, could you re-add this with appropriate sources, please?. Ths still applies; I have no problem with a useful mention and summary of the Berlin experiment. Add some good sources (presumably already lying, quivering in anticipation of further citation, at M-Bahn), and there's no problem. And if you do again use the text from that article, provide an attribution in your edit summary. — JohnFromPinckney (talk / edits) 09:45, 1 October 2024 (UTC)

@JohnFromPinckney: Fair enough, though again I would have thought a main article link would make where it was from self-evident. But it hardly matters, now. Anyway, thank you for replying (and my apologies for the lateness of this response); Regards, Moonraker12 (talk) 22:24, 31 October 2024 (UTC)