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0 degrees celsius + 0 degrees celsius -

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Re: 0 degrees celsius + 0 degrees celsius -

#21

Post by ugh »

_delirium wrote: post #19
nixme wrote: post #12

Earlier quoted context omitted.

Google can actually differentiate between the two meanings: degrees Celsius and Celsius degrees . As you explained, the query posed by the title is meaningless, but 0 degrees Celsius + 0 Celsius degrees is handled correctly: http://www.google.com/search?&q=0+degrees+celsius+%2B+0+...

Ah, that's pretty interesting. It makes sense when you read the two phrasings next to each other, but it does seem like a pretty subtle wording difference. I think in practice people tend to differentiate which one is meant by context more than by "degrees Celsius" versus "Celsius degrees" being used consistently. Should Google should convert the query somehow? It seems like adding two temperatures in degrees Celsius…

They should convert the query because that’s exactly what people want to know when they type in those kinds of queries.

Re: 0 degrees celsius + 0 degrees celsius -

#23

Post by ugh »

mhansen wrote: post #9

It's meaningless to add temperatures when the zero level is at +273. It's like adding years relative to 2010 years ago - it would be meaningless to add this year - 2010 - with (say) 1666 - the year of the Great Fire of London. It's meaningful to take differences (the Great Fire happened 344 years ago), but not to add. (Unless we converted to some kind of absolute time units e.g. years since the big bang) I'd say what…

Hm, well not really. It doesn’t give the answer the user wants to know. They should just convert the second degrees celsius to celsius degrees. (Ideally they should probably also add a ‘Did you mean …’-link with the alternative ála Wolfram Alpha.)

Re: 0 degrees celsius + 0 degrees celsius -

#25

Post by Twisol »

It sure looks really bizzare, but here it is broken down...

    "0 degrees celsius in kelvin"
      -> 0 degrees Celsius = 273.15 kelvin
    "273.15 kelvin + 273.15 kelvin in degrees Celsius"
      -> (273.15 kelvin) + (273.15 kelvin) = 273.15 degrees Celsius
Hence:

    "0 degrees celsius + 0 degrees celsius"
      -> (0 degrees Celsius) + (0 degrees Celsius) = 273.15 degrees Celsius

Re: 0 degrees celsius + 0 degrees celsius -

#27

Post by antileet »

_delirium wrote: post #7

It looks like it must be using kelvin as its canonical units: 0C + 0C = 273.15 K + 273.15 K = 546.3 K = 273.15 C The weirdness is that conversions like that don't work for units that have different zero points. Perhaps addition of temperatures isn't really well defined? If 273.15 K + 273.15 K does not equal 0 C + 0 C, despite 273.15 K = 0 C, it's not clear what addition "means" in this context. One restricted form of…

Seems it is easy enough to confuse even Wolfram Alpha

http://www.wolframalpha.com/input/?i=0+degrees+kelvin+%2B+0+...

Funnily enough the original query is handled well[1] by W|A:

http://www.wolframalpha.com/input/?i=0+degrees+celsius+%2B+0...

And the query that fails in Wolfram Alpha, works fine in Google's Calculator:

http://www.google.com/search?sourceid=chrome&ie=UTF-8&#3... :)

1: By "well", we probably mean according to intuition

Re: 0 degrees celsius + 0 degrees celsius -

#28

Post by momokatte »

[deleted] wrote: post #15
mhansen wrote: post #9

It's meaningless to add temperatures when the zero level is at +273. It's like adding years relative to 2010 years ago - it would be meaningless to add this year - 2010 - with (say) 1666 - the year of the Great Fire of London. It's meaningful to take differences (the Great Fire happened 344 years ago), but not to add. (Unless we converted to some kind of absolute time units e.g. years since the big bang) I'd say what…

[deleted]

"three degrees hotter" is an interval of three degrees, and not an absolute value along a scale. So you'd take your original temperature and add an interval of 3 degrees to it.

0 degrees Celsius has a heat value (273.15 K). If you double it (i.e. add 0 degrees Celsius to it), you get 546.3 K -- which is 273.15 degrees Celsius.

What it really comes down to is that if you're going to perform math on temperatures for scientific reasons, use Kelvin. And if you're adjusting a temperature by an interval, leave out the units from the math completely.

Re: 0 degrees celsius + 0 degrees celsius -

#29

Post by nixme »

_delirium wrote: post #19
nixme wrote: post #12

Earlier quoted context omitted.

Google can actually differentiate between the two meanings: degrees Celsius and Celsius degrees . As you explained, the query posed by the title is meaningless, but 0 degrees Celsius + 0 Celsius degrees is handled correctly: http://www.google.com/search?&q=0+degrees+celsius+%2B+0+...

Ah, that's pretty interesting. It makes sense when you read the two phrasings next to each other, but it does seem like a pretty subtle wording difference. I think in practice people tend to differentiate which one is meant by context more than by "degrees Celsius" versus "Celsius degrees" being used consistently. Should Google should convert the query somehow? It seems like adding two temperatures in degrees Celsius…

Yes, they should just convert. Or be annoyingly pedantic:

  Did you mean: 0 degrees Celsius + 0 *Celsius degrees*
:)

Re: 0 degrees celsius + 0 degrees celsius -

#30

Post by ugh »

momokatte wrote: post #28
[deleted] wrote: post #15

Earlier quoted context omitted.

[deleted]

"three degrees hotter" is an interval of three degrees, and not an absolute value along a scale. So you'd take your original temperature and add an interval of 3 degrees to it. 0 degrees Celsius has a heat value (273.15 K). If you double it (i.e. add 0 degrees Celsius to it), you get 546.3 K -- which is 273.15 degrees Celsius. What it really comes down to is that if you're going to perform math on temperatures for sc…

You are right, I was wrong, but I think Google’s behavior is less than optimal. See my new comment.
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