Arquivo da tag: movimento browniano

Movimento browniano ou movimento lucreciano?

“There’s a model, you should realise, 
A paradigm of this that’s dancing right before your eyes – 
For look well when you let the sun peep in a shuttered room 
Pouring forth the brilliance of its beams into the gloom, 
And you’ll see myriads of motes all moving in many ways 
Throughout the void and intermingling in the golden rays 
As if in everlasting struggle, battling in troops, 
Ceaselessly separating and regathering in groups. 
From this you can imagine all the motions that take place 
Among the atoms that are tossed about in empty space. 
For to a certain extent, it is possible for us to trace 
Greater things from trivial examples, and discern 
In them the train of knowledge. Another reason you should turn 
Your attention to the motes that drift and tumble in the light: 
Such turmoil means that there are secret motions, out of sight, 
That lie concealed in matter. For you’ll see the motes careen 
Off course, and then bounce back again, by means of blows unseen, 
Drifting now in this direction, now that, on every side. 
You may be sure this starts with atoms; they are what provide 
The base of this unrest. For atoms are moving on their own, 
Then small formations of them, nearest them in scale, are thrown 
Into agitation by unseen atomic blows, 
And these strike slightly larger clusters, and on and on it goes – 
A movement that begins on the atomic level, by slight 
Degrees ascends until it is perceptible to our sight, 
So that we can behold the dust-motes dancing in the sun, 
Although the blows that move them can’t be seen by anyone.”

Lucrécio (99 AC – 55 AC), De rerum natura, vol. II