<p>No metric is known that can tell you whether you're getting closer or not to a certain target. It's of course not impossible that such a metric might exist, but we do not know.</p>
<p>If such a metric existed, the discrete logarithm assumption for elliptic curves would be broken.</p>

CC BY-SA 4.0
2023-10-22T21:13:21.640Z
Alright now that I know the distance metrics is something which is not yet discovered, any suggestions on the most effective way to negate the poins without resetting itself to the inverse side would be great if you could explain it with an example...
Melwyn
CC BY-SA 4.0
2023-10-23T01:24:44.803Z
The negation of a point *(x, y)* is just *(x, -y)*.
Pieter Wuille
CC BY-SA 4.0
2023-10-22T12:56:12.050Z
2023-10-22T16:27:15.613Z
2023-10-22T16:27:15.613Z
Pieter Wuille
<p>I grasp the concept of point negation and addition quite well. Point negation involves taking a public key, inverting it, and adding it to a target. The resulting difference between the target and the arrived point constitutes the private key of the public key that was inverted and added to the target, correct? Now, the question arises: can we calculate the distance between one public key and another? By 'distance,' I mean, just as I mentioned earlier, the gap between the target public key and the arrived public key represents the private key of the number that was inverted and added to the target. In a similar vein, is it feasible to compute the distance between two public keys? When I mention 'distance,' I refer to any metric, including time, serving as a feedback system, a means to ascertain whether we are progressing or regressing on the elliptic curve points from a specific standpoint.</p>

CC BY-SA 4.0
2023-10-22T12:16:44.970Z
Yes, they are points on an elliptic curve, so they have an x and a y coordinate. However your line of inquiry doesn’t make any sense to me. What are you trying to do with the distance between public keys? You seem to think that this reveals something about the private keys, but you can’t get from the public keys to the private keys, so it does not.
Murch
<public-key><ecdsa>
Feedback system possible
Melwyn
# Feedback system possible

(Asked by: username_0 on 2023-10-22)

I grasp the concept of point negation and addition quite well. Point negation involves taking a public key, inverting it, and adding it to a target. The resulting difference between the target and the arrived point constitutes the private key of the public key that was inverted and added to the target, correct? Now, the question arises: can we calculate the distance between one public key and another? By 'distance,' I mean, just as I mentioned earlier, the gap between the target public key and the arrived public key represents the private key of the number that was inverted and added to the target. In a similar vein, is it feasible to compute the distance between two public keys? When I mention 'distance,' I refer to any metric, including time, serving as a feedback system, a means to ascertain whether we are progressing or regressing on the elliptic curve points from a specific standpoint.

**Tags:** public-key, ecdsa

> **Comments:**
> **username_1**: Yes, they are points on an elliptic curve, so they have an x and a y coordinate. However your line of inquiry doesn’t make any sense to me. What are you trying to do with the distance between public keys? You seem to think that this reveals something about the private keys, but you can’t get from the public keys to the private keys, so it does not.  

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## 1 answers

### Answer by username_2 on 2023-10-22. Score: 2

No metric is known that can tell you whether you're getting closer or not to a certain target. It's of course not impossible that such a metric might exist, but we do not know.

If such a metric existed, the discrete logarithm assumption for elliptic curves would be broken.

> **Comments:**
> **username_0**: Alright now that I know the distance metrics is something which is not yet discovered, any suggestions on the most effective way to negate the poins without resetting itself to the inverse side would be great if you could explain it with an example...  
> **username_2**: The negation of a point *(x, y)* is just *(x, -y)*.  

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