Why can we not "touch" things?

[Afraid of Time]

Can someone explain to me why according to physics we can never really touch anything? I'm talking about "touch" as in the sense.

[StringJunky]

Can someone explain to me why according to physics we can never really touch anything? I'm talking about "touch" as in the sense.

Touch in terms of physics, I think, is really electrostatic repulsion between the molecules of your body and the object being touched.The fields around the molecules that make up your skin repel other solid surfaces, which also have fields, so, in the real sense, there is no physical contact between the object surfaces. Imagine bringing the positive poles together of two magnets; the actual magnets don't touch before you feel resistance. This magnetic example is analogous to that phenomenon but instead there's a repelling electric charge involved from the outer electron shell of each molecule, The shell may be occupied ( -ve charge) or empty ( +ve charge). Like charges repel. In short, 'touch' is the resistance between electric fields and not the massive parts of molecules, like protons and neutrons. That field resistance is sent as an impulse to the brain.

Edited July 21, 2016 by StringJunky

[geordief]

Is there a more general definition of "touch" ?

 

If we send any signal to an object and the signal bounces back and is received at the source would that be called "touch"?

 

Or if we simply receive a signal from any source ,can we say we have "been in contact " with it?

[FromEarth]

I think you could touch things in a blackhole.

[Phi for All]

Can someone explain to me why according to physics we can never really touch anything? I'm talking about "touch" as in the sense.

 

If you're talking about "touch" as in the sense, of course you can touch things. For the sense, you don't need the physics description. Touch the sense is about relaying information to the brain like any other sense.

 

As to the question of why we can never really touch anything, StringJunky's reply is the answer "according to physics" you're looking for.

[Strange]

The fields around the molecules that make up your skin repel other solid surfaces, which also have fields, so, in the real sense, there is no physical contact between the object surfaces.

 

If you look at it that way, there are no object surfaces, just the fields!

[geordief]

 

If you look at it that way, there are no object surfaces, just the fields!

If objects had surfaces ,what would the surface look like? Smooth? Pitted? Symmetrical? Let's say "fractal" while we are at it.

 

Is there such a thing ,by the way as a discontinuous field?

Edited July 22, 2016 by geordief

[Strange]

If objects had surfaces ,what would the surface look like? Smooth? Pitted? Symmetrical? Let's say "fractal" while we are at it.

 

They would look like (fuzzier versions of) electron orbitals: http://www.nature.com/nchem/journal/v3/n4/fig_tab/nchem.1008_F3.html

 

 

Is there such a thing ,by the way as a discontinuous field?

 

Not sure.

[StringJunky]

Those of us who have more than the absolute basics know that touch is macro phenomenon and it's all , in fact, composed of fields and other sensorily intangible concepts but, I think, letting noobs think that nuclei are solid surrounded by little solid bits moving in a field is more easily comprehensible and illustrates what the OP wants to know. Saying to them "it's all fields" just raises more questions without getting to the point or you will lose them in the mire of technical information. Even though I know a bit more I still need it dumbing down myself when it goes beyond my own limits. The fact is, unless you are reading the latest journals you will never know the state of the current art.

If you look at it that way, there are no object surfaces, just the fields!

Edited July 22, 2016 by StringJunky

[Delta1212]

I still remember the first time I pushed down on the top of a table and realized that the resistance I was feeling was of a kind with the resistance felt when pressing magnets with the same charge together, just stronger over a shorter distance.

[sethoflagos]

Didn't I read somewhere recently that the dominant force preventing two objects from occupying the same space ('touching') was electron degeneracy pressure rather than electrostatic repulsion?

[Sriman Dutta]

Really inspired by this thread....Never thought of this before.