Degradation of Technology.

[daniel l.]

If a modern city was abandoned today and left to rot for 3 or 4 thousand years, Would the advanced technology have sufficiently decayed to make the city similar to the excavated ancient Cities that we see today? Such as Mycenae or Pergamon? Would we even be able to tell the difference?

[magnemoe]

Mostly depend on location. Many places in the Middle east would do magnitudes better than something in an damp area where you also have frost. Think Egypt. 
And you would find plenty of signs of advanced technology anyway, copper, aluminium and ceramic last a long time so do plastic if away from sunlight. 

One problem is that concrete and steel don't keep as well as stone and we build more optimized so the buildings themselves would be in far worse shape and you are unlikely to get many cool ruins. 
Bunkers and tunnels will probably be an exception. 

[Bill Phil]

You'll probably see the husks of ancient skyscrapers, if it hasn't decayed enormously. Roads might leave substantial evidence behind. 

Concrete structures, like parking garages, will probably stand a long time. Think Coliseum. And other concrete Roman buildings. They are decayed, but they're still around to an extent.

[fireblade274]

Just watched a TV show on this, a few thousand years (1-3k) later skyscrapers would begin crumbling and steel structures will begin to have rust holes, and after only 1k parking lots will begin to get eaten by the soil, but stone structures like mount Rushmore will last much, much MUCH longer 

[daniel l.]

How about the things that make us really stand out from those predecessors, Such as electricity and computers?

[Bill Phil]

Computers are pretty fragile, plastic, sensitive material, and the like are likely to be severely damaged. But something may survive.

Electricity...Power plant ruins, degraded cables, power line towers, and the like might be in ruins, but there.

[Atlas2342]

Adding to the topic, there is a television series on this:  https://en.m.wikipedia.org/wiki/Life_After_People

[kerbiloid]

51 minutes ago, daniel l. said:

How about the things that make us really stand out from those predecessors, Such as electricity and computers?

Have you ever met any of those famous ancient Ύντηλος PC or iZeus? The Time is ruthless... Only abacus and antikytherian still survived.

While the archaeologists are still unsuccessfully trying to decode the pictograms on Phaistos Disc. Which is just a cartridge for the ancient ΞΒοξ-360 game console,

[kerbiloid]

Why? That Phaistos pictos are just a walkthrough instruction for the ancient "Prince of Persia" game.
(And btw the ancient Persia wanted the game author dead or alive, paying a talent of gold.)

Edited May 14, 2016 by kerbiloid

[YNM]

I think the things to stand the longest are landscaping or something with massive amount of rocks/concrete. Canals, dams, bridge abutments and pillars, road embankment. Super advanced technology (anything metal or plastic) is going to either bend or broke - maybe it'll just cause a shift in magnetic field. Even so, the ones that last even longer should be... Satellites ?

Edited May 14, 2016 by YNM

[Kryten]

 You're not likely to find any big artifacts after that much time, but the little things can tell you a lot. There'd be plastic pieces everywhere; you're going to get some pieces of corrosion-resistant metals like aluminium, which can't practically be refined without electricity; you'd get the ceramic insulators from powerlines, and so on.

[magnemoe]

1 hour ago, Kryten said:

 You're not likely to find any big artifacts after that much time, but the little things can tell you a lot. There'd be plastic pieces everywhere; you're going to get some pieces of corrosion-resistant metals like aluminium, which can't practically be refined without electricity; you'd get the ceramic insulators from powerlines, and so on.

Yes, however climate is everything, bury an car or computer in the desert and you should be able to see that it is then you dig it up 4000 year later. 
In Egypt wood and paper get preserved over that time. In wetter climate not so much, most metal in WW2 bunkers in Europe has rusted away. 
Downside with large structures is that you cant really say much about technology level just that they are able to build large structures. 

[PB666]

Dry, cold, and buried deep, (generally away from the sun and with an ozone free oxide scavengers).

 

[magnemoe]

31 minutes ago, PB666 said:

Dry, cold, and buried deep, (generally away from the sun and with an ozone free oxide scavengers).

 

Dry and cold works even better but is far fewer people there than dry and hot areas. 

[Kryten]

There'd also be lots of glass. Glass is common enough in archeological sites already, but modern flat glass or toughened glass requires some pretty advanced tech, and would be present in enormous quantities.

Edited May 14, 2016 by Kryten

[Scotius]

Also items made from non-corroding, rare metals that do not exist naturally in pure form. Bits of titanium, iridium etc. And isotopes from our spent nuclear fuel. Some of them will outlast biosphere on Earth.

[pincushionman]

All I can think about reading this thread is a book called Motel of the Mysteries about the excavation if of some ancient "holy site" that is obviously a roadside hotel hundreds if years after the whole of the country of "Usa" was buried under ten feet of junk mail. And the very wrong assumptions the so-called archaeologists made about all the random stuff they found there.

As you probably guessed, it's not exactly an accurate treatment of what would actually last that long.

Edited May 14, 2016 by pincushionman

[cubinator]

On 5/14/2016 at 8:12 AM, PB666 said:

Dry, cold, and buried deep, (generally away from the sun and with an ozone free oxide scavengers).

 

Like our spent nuclear fuel storage caves? That'd be quite the sign of advanced civilization.

[LordFerret]

On 5/14/2016 at 1:39 AM, kerbiloid said:

While the archaeologists are still unsuccessfully trying to decode the pictograms on Phaistos Disc.

http://news.discovery.com/history/archaeology/mysterious-4000-year-old-cd-rom-code-cracked-141023.htm

[Scotius]

Without the knowledge of the language that was written down on the disc? Yeah, right. With a bit of mental gymnastic you can put anything as a result. I've read a russian book about Phaistos disc. Its author jokingly tried to decipher it using russian language. And you know what? The text he got actually made sense - it was something along the lines of: "To the Prince Mishuva - son of the Sea". Context is plausible too - honorifics such as this were in wide usage in the past, and Minoans were seafaring people to boot. Of course no one suggests Ancient Minoans spoke slavic language. I'm afraid until we find a bilingual text (Minoan-Hittite or Minoan-Egyptian) there will be no rock-solid interpretation of this inscription.

[James Kerman]

Hopefully no-one finds a Justin Beiber CD in 4000 years and thinks its the pinnacle of our society.

[kerbiloid]

6 hours ago, James Kerman said:

Hopefully no-one finds a Justin Beiber CD in 4000 years and thinks its the pinnacle of our society.

Happily, no. They will find Rammstein's scenery...