Fix typo in PEA tutorial =+ should be + (#4122)

jlapeyre · web-flow · commit 23fc901d1263 · 2025-10-23T19:02:15.000Z
There is an erroneous extra `=` in an equation. This PR removes it. For the correct expression, see, for example Eq (1) in [this paper](https://arxiv.org/pdf/1805.04492) ([abstract for same paper](https://arxiv.org/abs/1805.04492))
diff --git a/docs/tutorials/probabilistic-error-amplification.ipynb b/docs/tutorials/probabilistic-error-amplification.ipynb
@@ -47,7 +47,7 @@
     "It assumes expectation values scale with noise by a known function\n",
     "\n",
     "$$\n",
-    "\\langle A(\\lambda) \\rangle = \\langle A(0) \\rangle =+ \\sum_{k=0}^{m} a_k \\lambda^k + R\n",
+    "\\langle A(\\lambda) \\rangle = \\langle A(0) \\rangle + \\sum_{k=0}^{m} a_k \\lambda^k + R\n",
     "$$\n",
     "where $\\lambda$ parameterizes the noise strength and can be amplified."
    ]

Original file line number	Diff line number	Diff line change
`@@ -47,7 +47,7 @@`
`47`	`47`	`"It assumes expectation values scale with noise by a known function\n",`
`48`	`48`	`"\n",`
`49`	`49`	`"$$\n",`
`50`		`- "\\langle A(\\lambda) \\rangle = \\langle A(0) \\rangle =+ \\sum_{k=0}^{m} a_k \\lambda^k + R\n",`
	`50`	`+ "\\langle A(\\lambda) \\rangle = \\langle A(0) \\rangle + \\sum_{k=0}^{m} a_k \\lambda^k + R\n",`
`51`	`51`	`"$$\n",`
`52`	`52`	`"where $\\lambda$ parameterizes the noise strength and can be amplified."`
`53`	`53`	`]`