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| Type | Label | Description |
|---|---|---|
| Statement | ||
| Theorem | nmfval 24601* | The value of the norm function as the distance to zero. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑊) & ⊢ 𝑋 = (Base‘𝑊) & ⊢ 0 = (0g‘𝑊) & ⊢ 𝐷 = (dist‘𝑊) ⇒ ⊢ 𝑁 = (𝑥 ∈ 𝑋 ↦ (𝑥𝐷 0 )) | ||
| Theorem | nmval 24602 | The value of the norm as the distance to zero. Problem 1 of [Kreyszig] p. 63. (Contributed by NM, 4-Dec-2006.) (Revised by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑊) & ⊢ 𝑋 = (Base‘𝑊) & ⊢ 0 = (0g‘𝑊) & ⊢ 𝐷 = (dist‘𝑊) ⇒ ⊢ (𝐴 ∈ 𝑋 → (𝑁‘𝐴) = (𝐴𝐷 0 )) | ||
| Theorem | nmfval0 24603* | The value of the norm function on a structure containing a zero as the distance restricted to the elements of the base set to zero. Examples of structures containing a "zero" are groups (see nmfval2 24604 proved from this theorem and grpidcl 18983) or more generally monoids (see mndidcl 18762), or pointed sets). (Contributed by Mario Carneiro, 2-Oct-2015.) Extract this result from the proof of nmfval2 24604. (Revised by BJ, 27-Aug-2024.) |
| ⊢ 𝑁 = (norm‘𝑊) & ⊢ 𝑋 = (Base‘𝑊) & ⊢ 0 = (0g‘𝑊) & ⊢ 𝐷 = (dist‘𝑊) & ⊢ 𝐸 = (𝐷 ↾ (𝑋 × 𝑋)) ⇒ ⊢ ( 0 ∈ 𝑋 → 𝑁 = (𝑥 ∈ 𝑋 ↦ (𝑥𝐸 0 ))) | ||
| Theorem | nmfval2 24604* | The value of the norm function on a group as the distance restricted to the elements of the base set to zero. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑊) & ⊢ 𝑋 = (Base‘𝑊) & ⊢ 0 = (0g‘𝑊) & ⊢ 𝐷 = (dist‘𝑊) & ⊢ 𝐸 = (𝐷 ↾ (𝑋 × 𝑋)) ⇒ ⊢ (𝑊 ∈ Grp → 𝑁 = (𝑥 ∈ 𝑋 ↦ (𝑥𝐸 0 ))) | ||
| Theorem | nmval2 24605 | The value of the norm on a group as the distance restricted to the elements of the base set to zero. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑊) & ⊢ 𝑋 = (Base‘𝑊) & ⊢ 0 = (0g‘𝑊) & ⊢ 𝐷 = (dist‘𝑊) & ⊢ 𝐸 = (𝐷 ↾ (𝑋 × 𝑋)) ⇒ ⊢ ((𝑊 ∈ Grp ∧ 𝐴 ∈ 𝑋) → (𝑁‘𝐴) = (𝐴𝐸 0 )) | ||
| Theorem | nmf2 24606 | The norm on a metric group is a function from the base set into the reals. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑊) & ⊢ 𝑋 = (Base‘𝑊) & ⊢ 𝐷 = (dist‘𝑊) & ⊢ 𝐸 = (𝐷 ↾ (𝑋 × 𝑋)) ⇒ ⊢ ((𝑊 ∈ Grp ∧ 𝐸 ∈ (Met‘𝑋)) → 𝑁:𝑋⟶ℝ) | ||
| Theorem | nmpropd 24607 | Weak property deduction for a norm. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ (𝜑 → (Base‘𝐾) = (Base‘𝐿)) & ⊢ (𝜑 → (+g‘𝐾) = (+g‘𝐿)) & ⊢ (𝜑 → (dist‘𝐾) = (dist‘𝐿)) ⇒ ⊢ (𝜑 → (norm‘𝐾) = (norm‘𝐿)) | ||
| Theorem | nmpropd2 24608* | Strong property deduction for a norm. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ (𝜑 → 𝐵 = (Base‘𝐾)) & ⊢ (𝜑 → 𝐵 = (Base‘𝐿)) & ⊢ (𝜑 → 𝐾 ∈ Grp) & ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝐾)𝑦) = (𝑥(+g‘𝐿)𝑦)) & ⊢ (𝜑 → ((dist‘𝐾) ↾ (𝐵 × 𝐵)) = ((dist‘𝐿) ↾ (𝐵 × 𝐵))) ⇒ ⊢ (𝜑 → (norm‘𝐾) = (norm‘𝐿)) | ||
| Theorem | isngp 24609 | The property of being a normed group. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ (𝐺 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ 𝐺 ∈ MetSp ∧ (𝑁 ∘ − ) ⊆ 𝐷)) | ||
| Theorem | isngp2 24610 | The property of being a normed group. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝐸 = (𝐷 ↾ (𝑋 × 𝑋)) ⇒ ⊢ (𝐺 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ 𝐺 ∈ MetSp ∧ (𝑁 ∘ − ) = 𝐸)) | ||
| Theorem | isngp3 24611* | The property of being a normed group. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) & ⊢ 𝑋 = (Base‘𝐺) ⇒ ⊢ (𝐺 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ 𝐺 ∈ MetSp ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝑥𝐷𝑦) = (𝑁‘(𝑥 − 𝑦)))) | ||
| Theorem | ngpgrp 24612 | A normed group is a group. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ (𝐺 ∈ NrmGrp → 𝐺 ∈ Grp) | ||
| Theorem | ngpms 24613 | A normed group is a metric space. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ (𝐺 ∈ NrmGrp → 𝐺 ∈ MetSp) | ||
| Theorem | ngpxms 24614 | A normed group is an extended metric space. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ (𝐺 ∈ NrmGrp → 𝐺 ∈ ∞MetSp) | ||
| Theorem | ngptps 24615 | A normed group is a topological space. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ (𝐺 ∈ NrmGrp → 𝐺 ∈ TopSp) | ||
| Theorem | ngpmet 24616 | The (induced) metric of a normed group is a metric. Part of Definition 2.2-1 of [Kreyszig] p. 58. (Contributed by NM, 4-Dec-2006.) (Revised by AV, 14-Oct-2021.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝐷 = ((dist‘𝐺) ↾ (𝑋 × 𝑋)) ⇒ ⊢ (𝐺 ∈ NrmGrp → 𝐷 ∈ (Met‘𝑋)) | ||
| Theorem | ngpds 24617 | Value of the distance function in terms of the norm of a normed group. Equation 1 of [Kreyszig] p. 59. (Contributed by NM, 28-Nov-2006.) (Revised by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝐺) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝐴𝐷𝐵) = (𝑁‘(𝐴 − 𝐵))) | ||
| Theorem | ngpdsr 24618 | Value of the distance function in terms of the norm of a normed group. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝐺) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝐴𝐷𝐵) = (𝑁‘(𝐵 − 𝐴))) | ||
| Theorem | ngpds2 24619 | Write the distance between two points in terms of distance from zero. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 0 = (0g‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝐴𝐷𝐵) = ((𝐴 − 𝐵)𝐷 0 )) | ||
| Theorem | ngpds2r 24620 | Write the distance between two points in terms of distance from zero. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 0 = (0g‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝐴𝐷𝐵) = ((𝐵 − 𝐴)𝐷 0 )) | ||
| Theorem | ngpds3 24621 | Write the distance between two points in terms of distance from zero. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 0 = (0g‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝐴𝐷𝐵) = ( 0 𝐷(𝐴 − 𝐵))) | ||
| Theorem | ngpds3r 24622 | Write the distance between two points in terms of distance from zero. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 0 = (0g‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝐴𝐷𝐵) = ( 0 𝐷(𝐵 − 𝐴))) | ||
| Theorem | ngprcan 24623 | Cancel right addition inside a distance calculation. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ + = (+g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ (𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((𝐴 + 𝐶)𝐷(𝐵 + 𝐶)) = (𝐴𝐷𝐵)) | ||
| Theorem | ngplcan 24624 | Cancel left addition inside a distance calculation. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ + = (+g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ (((𝐺 ∈ NrmGrp ∧ 𝐺 ∈ Abel) ∧ (𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((𝐶 + 𝐴)𝐷(𝐶 + 𝐵)) = (𝐴𝐷𝐵)) | ||
| Theorem | isngp4 24625* | Express the property of being a normed group purely in terms of right-translation invariance of the metric instead of using the definition of norm (which itself uses the metric). (Contributed by Mario Carneiro, 29-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ + = (+g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ (𝐺 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ 𝐺 ∈ MetSp ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ∀𝑧 ∈ 𝑋 ((𝑥 + 𝑧)𝐷(𝑦 + 𝑧)) = (𝑥𝐷𝑦))) | ||
| Theorem | ngpinvds 24626 | Two elements are the same distance apart as their inverses. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝐼 = (invg‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ (((𝐺 ∈ NrmGrp ∧ 𝐺 ∈ Abel) ∧ (𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋)) → ((𝐼‘𝐴)𝐷(𝐼‘𝐵)) = (𝐴𝐷𝐵)) | ||
| Theorem | ngpsubcan 24627 | Cancel right subtraction inside a distance calculation. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (dist‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ (𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((𝐴 − 𝐶)𝐷(𝐵 − 𝐶)) = (𝐴𝐷𝐵)) | ||
| Theorem | nmf 24628 | The norm on a normed group is a function into the reals. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) ⇒ ⊢ (𝐺 ∈ NrmGrp → 𝑁:𝑋⟶ℝ) | ||
| Theorem | nmcl 24629 | The norm of a normed group is closed in the reals. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋) → (𝑁‘𝐴) ∈ ℝ) | ||
| Theorem | nmge0 24630 | The norm of a normed group is nonnegative. Second part of Problem 2 of [Kreyszig] p. 64. (Contributed by NM, 28-Nov-2006.) (Revised by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋) → 0 ≤ (𝑁‘𝐴)) | ||
| Theorem | nmeq0 24631 | The identity is the only element of the group with zero norm. First part of Problem 2 of [Kreyszig] p. 64. (Contributed by NM, 24-Nov-2006.) (Revised by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 0 = (0g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋) → ((𝑁‘𝐴) = 0 ↔ 𝐴 = 0 )) | ||
| Theorem | nmne0 24632 | The norm of a nonzero element is nonzero. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 0 = (0g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐴 ≠ 0 ) → (𝑁‘𝐴) ≠ 0) | ||
| Theorem | nmrpcl 24633 | The norm of a nonzero element is a positive real. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 0 = (0g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐴 ≠ 0 ) → (𝑁‘𝐴) ∈ ℝ+) | ||
| Theorem | nminv 24634 | The norm of a negated element is the same as the norm of the original element. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 𝐼 = (invg‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋) → (𝑁‘(𝐼‘𝐴)) = (𝑁‘𝐴)) | ||
| Theorem | nmmtri 24635 | The triangle inequality for the norm of a subtraction. (Contributed by NM, 27-Dec-2007.) (Revised by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ − = (-g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝑁‘(𝐴 − 𝐵)) ≤ ((𝑁‘𝐴) + (𝑁‘𝐵))) | ||
| Theorem | nmsub 24636 | The norm of the difference between two elements. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ − = (-g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝑁‘(𝐴 − 𝐵)) = (𝑁‘(𝐵 − 𝐴))) | ||
| Theorem | nmrtri 24637 | Reverse triangle inequality for the norm of a subtraction. Problem 3 of [Kreyszig] p. 64. (Contributed by NM, 4-Dec-2006.) (Revised by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ − = (-g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (abs‘((𝑁‘𝐴) − (𝑁‘𝐵))) ≤ (𝑁‘(𝐴 − 𝐵))) | ||
| Theorem | nm2dif 24638 | Inequality for the difference of norms. (Contributed by Mario Carneiro, 6-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ − = (-g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → ((𝑁‘𝐴) − (𝑁‘𝐵)) ≤ (𝑁‘(𝐴 − 𝐵))) | ||
| Theorem | nmtri 24639 | The triangle inequality for the norm of a sum. (Contributed by NM, 11-Nov-2006.) (Revised by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ + = (+g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝑁‘(𝐴 + 𝐵)) ≤ ((𝑁‘𝐴) + (𝑁‘𝐵))) | ||
| Theorem | nmtri2 24640 | Triangle inequality for the norm of two subtractions. (Contributed by NM, 24-Feb-2008.) (Revised by AV, 8-Oct-2021.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ − = (-g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ (𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → (𝑁‘(𝐴 − 𝐶)) ≤ ((𝑁‘(𝐴 − 𝐵)) + (𝑁‘(𝐵 − 𝐶)))) | ||
| Theorem | ngpi 24641* | The properties of a normed group, which is a group accompanied by a norm. (Contributed by AV, 7-Oct-2021.) |
| ⊢ 𝑉 = (Base‘𝑊) & ⊢ 𝑁 = (norm‘𝑊) & ⊢ − = (-g‘𝑊) & ⊢ 0 = (0g‘𝑊) ⇒ ⊢ (𝑊 ∈ NrmGrp → (𝑊 ∈ Grp ∧ 𝑁:𝑉⟶ℝ ∧ ∀𝑥 ∈ 𝑉 (((𝑁‘𝑥) = 0 ↔ 𝑥 = 0 ) ∧ ∀𝑦 ∈ 𝑉 (𝑁‘(𝑥 − 𝑦)) ≤ ((𝑁‘𝑥) + (𝑁‘𝑦))))) | ||
| Theorem | nm0 24642 | Norm of the identity element. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝐺) & ⊢ 0 = (0g‘𝐺) ⇒ ⊢ (𝐺 ∈ NrmGrp → (𝑁‘ 0 ) = 0) | ||
| Theorem | nmgt0 24643 | The norm of a nonzero element is a positive real. (Contributed by NM, 20-Nov-2007.) (Revised by AV, 8-Oct-2021.) |
| ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 0 = (0g‘𝐺) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ 𝑋) → (𝐴 ≠ 0 ↔ 0 < (𝑁‘𝐴))) | ||
| Theorem | sgrim 24644 | The induced metric on a subgroup is the induced metric on the parent group equipped with a norm. (Contributed by NM, 1-Feb-2008.) (Revised by AV, 19-Oct-2021.) |
| ⊢ 𝑋 = (𝑇 ↾s 𝑈) & ⊢ 𝐷 = (dist‘𝑇) & ⊢ 𝐸 = (dist‘𝑋) ⇒ ⊢ (𝑈 ∈ 𝑆 → 𝐸 = 𝐷) | ||
| Theorem | sgrimval 24645 | The induced metric on a subgroup in terms of the induced metric on the parent normed group. (Contributed by NM, 1-Feb-2008.) (Revised by AV, 19-Oct-2021.) |
| ⊢ 𝑋 = (𝑇 ↾s 𝑈) & ⊢ 𝐷 = (dist‘𝑇) & ⊢ 𝐸 = (dist‘𝑋) & ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 𝑆 = (SubGrp‘𝑇) ⇒ ⊢ (((𝐺 ∈ NrmGrp ∧ 𝑈 ∈ 𝑆) ∧ (𝐴 ∈ 𝑈 ∧ 𝐵 ∈ 𝑈)) → (𝐴𝐸𝐵) = (𝐴𝐷𝐵)) | ||
| Theorem | subgnm 24646 | The norm in a subgroup. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝐻 = (𝐺 ↾s 𝐴) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 𝑀 = (norm‘𝐻) ⇒ ⊢ (𝐴 ∈ (SubGrp‘𝐺) → 𝑀 = (𝑁 ↾ 𝐴)) | ||
| Theorem | subgnm2 24647 | A substructure assigns the same values to the norms of elements of a subgroup. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝐻 = (𝐺 ↾s 𝐴) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 𝑀 = (norm‘𝐻) ⇒ ⊢ ((𝐴 ∈ (SubGrp‘𝐺) ∧ 𝑋 ∈ 𝐴) → (𝑀‘𝑋) = (𝑁‘𝑋)) | ||
| Theorem | subgngp 24648 | A normed group restricted to a subgroup is a normed group. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝐻 = (𝐺 ↾s 𝐴) ⇒ ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐴 ∈ (SubGrp‘𝐺)) → 𝐻 ∈ NrmGrp) | ||
| Theorem | ngptgp 24649 | A normed abelian group is a topological group (with the topology induced by the metric induced by the norm). (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ ((𝐺 ∈ NrmGrp ∧ 𝐺 ∈ Abel) → 𝐺 ∈ TopGrp) | ||
| Theorem | ngppropd 24650* | Property deduction for a normed group. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ (𝜑 → 𝐵 = (Base‘𝐾)) & ⊢ (𝜑 → 𝐵 = (Base‘𝐿)) & ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝑥(+g‘𝐾)𝑦) = (𝑥(+g‘𝐿)𝑦)) & ⊢ (𝜑 → ((dist‘𝐾) ↾ (𝐵 × 𝐵)) = ((dist‘𝐿) ↾ (𝐵 × 𝐵))) & ⊢ (𝜑 → (TopOpen‘𝐾) = (TopOpen‘𝐿)) ⇒ ⊢ (𝜑 → (𝐾 ∈ NrmGrp ↔ 𝐿 ∈ NrmGrp)) | ||
| Theorem | reldmtng 24651 | The function toNrmGrp is a two-argument function. (Contributed by Mario Carneiro, 8-Oct-2015.) |
| ⊢ Rel dom toNrmGrp | ||
| Theorem | tngval 24652 | Value of the function which augments a given structure 𝐺 with a norm 𝑁. (Contributed by Mario Carneiro, 2-Oct-2015.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ − = (-g‘𝐺) & ⊢ 𝐷 = (𝑁 ∘ − ) & ⊢ 𝐽 = (MetOpen‘𝐷) ⇒ ⊢ ((𝐺 ∈ 𝑉 ∧ 𝑁 ∈ 𝑊) → 𝑇 = ((𝐺 sSet 〈(dist‘ndx), 𝐷〉) sSet 〈(TopSet‘ndx), 𝐽〉)) | ||
| Theorem | tnglem 24653 | Lemma for tngbas 24655 and similar theorems. (Contributed by Mario Carneiro, 2-Oct-2015.) (Revised by AV, 31-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝐸 = Slot (𝐸‘ndx) & ⊢ (𝐸‘ndx) ≠ (TopSet‘ndx) & ⊢ (𝐸‘ndx) ≠ (dist‘ndx) ⇒ ⊢ (𝑁 ∈ 𝑉 → (𝐸‘𝐺) = (𝐸‘𝑇)) | ||
| Theorem | tnglemOLD 24654 | Obsolete version of tnglem 24653 as of 31-Oct-2024. Lemma for tngbas 24655 and similar theorems. (Contributed by Mario Carneiro, 2-Oct-2015.) (New usage is discouraged.) (Proof modification is discouraged.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝐸 = Slot 𝐾 & ⊢ 𝐾 ∈ ℕ & ⊢ 𝐾 < 9 ⇒ ⊢ (𝑁 ∈ 𝑉 → (𝐸‘𝐺) = (𝐸‘𝑇)) | ||
| Theorem | tngbas 24655 | The base set of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (Revised by AV, 31-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝐵 = (Base‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → 𝐵 = (Base‘𝑇)) | ||
| Theorem | tngbasOLD 24656 | Obsolete version of tngbas 24655 as of 31-Oct-2024. The base set of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (New usage is discouraged.) (Proof modification is discouraged.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝐵 = (Base‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → 𝐵 = (Base‘𝑇)) | ||
| Theorem | tngplusg 24657 | The group addition of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (Revised by AV, 31-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ + = (+g‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → + = (+g‘𝑇)) | ||
| Theorem | tngplusgOLD 24658 | Obsolete version of tngplusg 24657 as of 31-Oct-2024. The group addition of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (New usage is discouraged.) (Proof modification is discouraged.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ + = (+g‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → + = (+g‘𝑇)) | ||
| Theorem | tng0 24659 | The group identity of a structure augmented with a norm. (Contributed by Mario Carneiro, 4-Oct-2015.) (Revised by AV, 31-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 0 = (0g‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → 0 = (0g‘𝑇)) | ||
| Theorem | tngmulr 24660 | The ring multiplication of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (Revised by AV, 31-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ · = (.r‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → · = (.r‘𝑇)) | ||
| Theorem | tngmulrOLD 24661 | Obsolete version of tngmulr 24660 as of 31-Oct-2024. The ring multiplication of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (New usage is discouraged.) (Proof modification is discouraged.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ · = (.r‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → · = (.r‘𝑇)) | ||
| Theorem | tngsca 24662 | The scalar ring of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (Revised by AV, 31-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝐹 = (Scalar‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → 𝐹 = (Scalar‘𝑇)) | ||
| Theorem | tngscaOLD 24663 | Obsolete version of tngsca 24662 as of 31-Oct-2024. The scalar ring of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (New usage is discouraged.) (Proof modification is discouraged.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝐹 = (Scalar‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → 𝐹 = (Scalar‘𝑇)) | ||
| Theorem | tngvsca 24664 | The scalar multiplication of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (Revised by AV, 31-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ · = ( ·𝑠 ‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → · = ( ·𝑠 ‘𝑇)) | ||
| Theorem | tngvscaOLD 24665 | Obsolete version of tngvsca 24664 as of 31-Oct-2024. The scalar multiplication of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (New usage is discouraged.) (Proof modification is discouraged.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ · = ( ·𝑠 ‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → · = ( ·𝑠 ‘𝑇)) | ||
| Theorem | tngip 24666 | The inner product operation of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (Revised by AV, 31-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ , = (·𝑖‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → , = (·𝑖‘𝑇)) | ||
| Theorem | tngipOLD 24667 | Obsolete version of tngip 24666 as of 31-Oct-2024. The inner product operation of a structure augmented with a norm. (Contributed by Mario Carneiro, 2-Oct-2015.) (New usage is discouraged.) (Proof modification is discouraged.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ , = (·𝑖‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → , = (·𝑖‘𝑇)) | ||
| Theorem | tngds 24668 | The metric function of a structure augmented with a norm. (Contributed by Mario Carneiro, 3-Oct-2015.) (Proof shortened by AV, 29-Oct-2024.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ − = (-g‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → (𝑁 ∘ − ) = (dist‘𝑇)) | ||
| Theorem | tngdsOLD 24669 | Obsolete version of tngds 24668 as of 29-Oct-2024. The metric function of a structure augmented with a norm. (Contributed by Mario Carneiro, 3-Oct-2015.) (Proof modification is discouraged.) (New usage is discouraged.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ − = (-g‘𝐺) ⇒ ⊢ (𝑁 ∈ 𝑉 → (𝑁 ∘ − ) = (dist‘𝑇)) | ||
| Theorem | tngtset 24670 | The topology generated by a normed structure. (Contributed by Mario Carneiro, 3-Oct-2015.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝐷 = (dist‘𝑇) & ⊢ 𝐽 = (MetOpen‘𝐷) ⇒ ⊢ ((𝐺 ∈ 𝑉 ∧ 𝑁 ∈ 𝑊) → 𝐽 = (TopSet‘𝑇)) | ||
| Theorem | tngtopn 24671 | The topology generated by a normed structure. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝐷 = (dist‘𝑇) & ⊢ 𝐽 = (MetOpen‘𝐷) ⇒ ⊢ ((𝐺 ∈ 𝑉 ∧ 𝑁 ∈ 𝑊) → 𝐽 = (TopOpen‘𝑇)) | ||
| Theorem | tngnm 24672 | The topology generated by a normed structure. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝐴 ∈ V ⇒ ⊢ ((𝐺 ∈ Grp ∧ 𝑁:𝑋⟶𝐴) → 𝑁 = (norm‘𝑇)) | ||
| Theorem | tngngp2 24673 | A norm turns a group into a normed group iff the generated metric is in fact a metric. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝐷 = (dist‘𝑇) ⇒ ⊢ (𝑁:𝑋⟶ℝ → (𝑇 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ 𝐷 ∈ (Met‘𝑋)))) | ||
| Theorem | tngngpd 24674* | Derive the axioms for a normed group from the axioms for a metric space. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 0 = (0g‘𝐺) & ⊢ (𝜑 → 𝐺 ∈ Grp) & ⊢ (𝜑 → 𝑁:𝑋⟶ℝ) & ⊢ ((𝜑 ∧ 𝑥 ∈ 𝑋) → ((𝑁‘𝑥) = 0 ↔ 𝑥 = 0 )) & ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝑁‘(𝑥 − 𝑦)) ≤ ((𝑁‘𝑥) + (𝑁‘𝑦))) ⇒ ⊢ (𝜑 → 𝑇 ∈ NrmGrp) | ||
| Theorem | tngngp 24675* | Derive the axioms for a normed group from the axioms for a metric space. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ − = (-g‘𝐺) & ⊢ 0 = (0g‘𝐺) ⇒ ⊢ (𝑁:𝑋⟶ℝ → (𝑇 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ ∀𝑥 ∈ 𝑋 (((𝑁‘𝑥) = 0 ↔ 𝑥 = 0 ) ∧ ∀𝑦 ∈ 𝑋 (𝑁‘(𝑥 − 𝑦)) ≤ ((𝑁‘𝑥) + (𝑁‘𝑦)))))) | ||
| Theorem | tnggrpr 24676 | If a structure equipped with a norm is a normed group, the structure itself must be a group. (Contributed by AV, 15-Oct-2021.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) ⇒ ⊢ ((𝑁 ∈ 𝑉 ∧ 𝑇 ∈ NrmGrp) → 𝐺 ∈ Grp) | ||
| Theorem | tngngp3 24677* | Alternate definition of a normed group (i.e., a group equipped with a norm) without using the properties of a metric space. This corresponds to the definition in N. H. Bingham, A. J. Ostaszewski: "Normed versus topological groups: dichotomy and duality", 2010, Dissertationes Mathematicae 472, pp. 1-138 and E. Deza, M.M. Deza: "Dictionary of Distances", Elsevier, 2006. (Contributed by AV, 16-Oct-2021.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ 0 = (0g‘𝐺) & ⊢ + = (+g‘𝐺) & ⊢ 𝐼 = (invg‘𝐺) ⇒ ⊢ (𝑁:𝑋⟶ℝ → (𝑇 ∈ NrmGrp ↔ (𝐺 ∈ Grp ∧ ∀𝑥 ∈ 𝑋 (((𝑁‘𝑥) = 0 ↔ 𝑥 = 0 ) ∧ (𝑁‘(𝐼‘𝑥)) = (𝑁‘𝑥) ∧ ∀𝑦 ∈ 𝑋 (𝑁‘(𝑥 + 𝑦)) ≤ ((𝑁‘𝑥) + (𝑁‘𝑦)))))) | ||
| Theorem | nrmtngdist 24678 | The augmentation of a normed group by its own norm has the same distance function as the normed group (restricted to the base set). (Contributed by AV, 15-Oct-2021.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp (norm‘𝐺)) & ⊢ 𝑋 = (Base‘𝐺) ⇒ ⊢ (𝐺 ∈ NrmGrp → (dist‘𝑇) = ((dist‘𝐺) ↾ (𝑋 × 𝑋))) | ||
| Theorem | nrmtngnrm 24679 | The augmentation of a normed group by its own norm is a normed group with the same norm. (Contributed by AV, 15-Oct-2021.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp (norm‘𝐺)) ⇒ ⊢ (𝐺 ∈ NrmGrp → (𝑇 ∈ NrmGrp ∧ (norm‘𝑇) = (norm‘𝐺))) | ||
| Theorem | tngngpim 24680 | The induced metric of a normed group is a function. (Contributed by AV, 19-Oct-2021.) |
| ⊢ 𝑇 = (𝐺 toNrmGrp 𝑁) & ⊢ 𝑁 = (norm‘𝐺) & ⊢ 𝑋 = (Base‘𝐺) & ⊢ 𝐷 = (dist‘𝑇) ⇒ ⊢ (𝐺 ∈ NrmGrp → 𝐷:(𝑋 × 𝑋)⟶ℝ) | ||
| Theorem | isnrg 24681 | A normed ring is a ring with a norm that makes it into a normed group, and such that the norm is an absolute value on the ring. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑅) & ⊢ 𝐴 = (AbsVal‘𝑅) ⇒ ⊢ (𝑅 ∈ NrmRing ↔ (𝑅 ∈ NrmGrp ∧ 𝑁 ∈ 𝐴)) | ||
| Theorem | nrgabv 24682 | The norm of a normed ring is an absolute value. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑅) & ⊢ 𝐴 = (AbsVal‘𝑅) ⇒ ⊢ (𝑅 ∈ NrmRing → 𝑁 ∈ 𝐴) | ||
| Theorem | nrgngp 24683 | A normed ring is a normed group. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ (𝑅 ∈ NrmRing → 𝑅 ∈ NrmGrp) | ||
| Theorem | nrgring 24684 | A normed ring is a ring. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ (𝑅 ∈ NrmRing → 𝑅 ∈ Ring) | ||
| Theorem | nmmul 24685 | The norm of a product in a normed ring. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝑅) & ⊢ 𝑁 = (norm‘𝑅) & ⊢ · = (.r‘𝑅) ⇒ ⊢ ((𝑅 ∈ NrmRing ∧ 𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋) → (𝑁‘(𝐴 · 𝐵)) = ((𝑁‘𝐴) · (𝑁‘𝐵))) | ||
| Theorem | nrgdsdi 24686 | Distribute a distance calculation. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝑅) & ⊢ 𝑁 = (norm‘𝑅) & ⊢ · = (.r‘𝑅) & ⊢ 𝐷 = (dist‘𝑅) ⇒ ⊢ ((𝑅 ∈ NrmRing ∧ (𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((𝑁‘𝐴) · (𝐵𝐷𝐶)) = ((𝐴 · 𝐵)𝐷(𝐴 · 𝐶))) | ||
| Theorem | nrgdsdir 24687 | Distribute a distance calculation. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝑅) & ⊢ 𝑁 = (norm‘𝑅) & ⊢ · = (.r‘𝑅) & ⊢ 𝐷 = (dist‘𝑅) ⇒ ⊢ ((𝑅 ∈ NrmRing ∧ (𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑋 ∧ 𝐶 ∈ 𝑋)) → ((𝐴𝐷𝐵) · (𝑁‘𝐶)) = ((𝐴 · 𝐶)𝐷(𝐵 · 𝐶))) | ||
| Theorem | nm1 24688 | The norm of one in a nonzero normed ring. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑅) & ⊢ 1 = (1r‘𝑅) ⇒ ⊢ ((𝑅 ∈ NrmRing ∧ 𝑅 ∈ NzRing) → (𝑁‘ 1 ) = 1) | ||
| Theorem | unitnmn0 24689 | The norm of a unit is nonzero in a nonzero normed ring. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑅) & ⊢ 𝑈 = (Unit‘𝑅) ⇒ ⊢ ((𝑅 ∈ NrmRing ∧ 𝑅 ∈ NzRing ∧ 𝐴 ∈ 𝑈) → (𝑁‘𝐴) ≠ 0) | ||
| Theorem | nminvr 24690 | The norm of an inverse in a nonzero normed ring. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ 𝑁 = (norm‘𝑅) & ⊢ 𝑈 = (Unit‘𝑅) & ⊢ 𝐼 = (invr‘𝑅) ⇒ ⊢ ((𝑅 ∈ NrmRing ∧ 𝑅 ∈ NzRing ∧ 𝐴 ∈ 𝑈) → (𝑁‘(𝐼‘𝐴)) = (1 / (𝑁‘𝐴))) | ||
| Theorem | nmdvr 24691 | The norm of a division in a nonzero normed ring. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ 𝑋 = (Base‘𝑅) & ⊢ 𝑁 = (norm‘𝑅) & ⊢ 𝑈 = (Unit‘𝑅) & ⊢ / = (/r‘𝑅) ⇒ ⊢ (((𝑅 ∈ NrmRing ∧ 𝑅 ∈ NzRing) ∧ (𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑈)) → (𝑁‘(𝐴 / 𝐵)) = ((𝑁‘𝐴) / (𝑁‘𝐵))) | ||
| Theorem | nrgdomn 24692 | A nonzero normed ring is a domain. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ (𝑅 ∈ NrmRing → (𝑅 ∈ Domn ↔ 𝑅 ∈ NzRing)) | ||
| Theorem | nrgtgp 24693 | A normed ring is a topological group. (Contributed by Mario Carneiro, 5-Oct-2015.) |
| ⊢ (𝑅 ∈ NrmRing → 𝑅 ∈ TopGrp) | ||
| Theorem | subrgnrg 24694 | A normed ring restricted to a subring is a normed ring. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝐻 = (𝐺 ↾s 𝐴) ⇒ ⊢ ((𝐺 ∈ NrmRing ∧ 𝐴 ∈ (SubRing‘𝐺)) → 𝐻 ∈ NrmRing) | ||
| Theorem | tngnrg 24695 | Given any absolute value over a ring, augmenting the ring with the absolute value produces a normed ring. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑇 = (𝑅 toNrmGrp 𝐹) & ⊢ 𝐴 = (AbsVal‘𝑅) ⇒ ⊢ (𝐹 ∈ 𝐴 → 𝑇 ∈ NrmRing) | ||
| Theorem | isnlm 24696* | A normed (left) module is a module which is also a normed group over a normed ring, such that the norm distributes over scalar multiplication. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑉 = (Base‘𝑊) & ⊢ 𝑁 = (norm‘𝑊) & ⊢ · = ( ·𝑠 ‘𝑊) & ⊢ 𝐹 = (Scalar‘𝑊) & ⊢ 𝐾 = (Base‘𝐹) & ⊢ 𝐴 = (norm‘𝐹) ⇒ ⊢ (𝑊 ∈ NrmMod ↔ ((𝑊 ∈ NrmGrp ∧ 𝑊 ∈ LMod ∧ 𝐹 ∈ NrmRing) ∧ ∀𝑥 ∈ 𝐾 ∀𝑦 ∈ 𝑉 (𝑁‘(𝑥 · 𝑦)) = ((𝐴‘𝑥) · (𝑁‘𝑦)))) | ||
| Theorem | nmvs 24697 | Defining property of a normed module. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝑉 = (Base‘𝑊) & ⊢ 𝑁 = (norm‘𝑊) & ⊢ · = ( ·𝑠 ‘𝑊) & ⊢ 𝐹 = (Scalar‘𝑊) & ⊢ 𝐾 = (Base‘𝐹) & ⊢ 𝐴 = (norm‘𝐹) ⇒ ⊢ ((𝑊 ∈ NrmMod ∧ 𝑋 ∈ 𝐾 ∧ 𝑌 ∈ 𝑉) → (𝑁‘(𝑋 · 𝑌)) = ((𝐴‘𝑋) · (𝑁‘𝑌))) | ||
| Theorem | nlmngp 24698 | A normed module is a normed group. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ (𝑊 ∈ NrmMod → 𝑊 ∈ NrmGrp) | ||
| Theorem | nlmlmod 24699 | A normed module is a left module. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ (𝑊 ∈ NrmMod → 𝑊 ∈ LMod) | ||
| Theorem | nlmnrg 24700 | The scalar component of a left module is a normed ring. (Contributed by Mario Carneiro, 4-Oct-2015.) |
| ⊢ 𝐹 = (Scalar‘𝑊) ⇒ ⊢ (𝑊 ∈ NrmMod → 𝐹 ∈ NrmRing) | ||
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